On-the-Job training

by Maria Jane Poncardas

    When I was scrolling through my documents in Physics. I stumbled upon the daily journals of my on-the-job training weekly experiences as we were mandated to write our journey. I thought I would share my immersion experience in the National Institute of Physics, University of the Philippines - Diliman through this blog as it is a precious moment in my physics life.

    When we were looking for a company and laboratory to have our OJTs, we were encouraged by our seniors to gain relevant research skills through the Condensed Matter Physics laboratory (CMPL) in National Institute of Physics, UP Diliman, since the physics laboratory in our university (Mindanao State University - Iligan Institute of Technology) has a solid foundation in the field of Materials Science research. We have bountiful of options to choose from the National Institute of Physics, as they are engaged in various research areas: condensed matter, instrumentation, photonics, plasma, structure & dynamics and fields & particle physics. The condensed matter physics laboratory is further split into semiconductor and superconductor groups. In our case, we chose superconductor group, due to referrals and influence of colleagues, (Hey, I was working with the Biophysics group in MSU-IIT). Furthermore, it is one of the group that has developed a program especially for the physics undergraduate students from different universities in the Philippines and provide an opportunity to learn and experience scientific research on super conductivity and nanotechnology. Interesting, right?

Upon application to their Summer Immersion Program 2014, we were informed that the program will no longer provide funding from DOST, unlike from previous years. We were somehow disappointed since we have to pay for everything such as flights and dorms, but regardless of this circumstance, that didn't stop us from joining them since we were more enthused by the training that they will impart to us, and we believed that it would be a life-changing experience.

Hence, the application continues and we no longer need to have an interview online but that the acceptance process would depend heavily on the requirements we provided them. I was thrilled to have heard of my application being accepted and my family was delighted and supported me throughout all my needs.

This On-the-Job Training (PHYS 197 Practicum) is a part of our curriculum in Bachelor of Science in Physics and is done during our third year of scholastic accomplishment, summer. Partial fulfillment of such coursework is to have a written activities undertaken per day, new insights learned and problems encountered.


WEEK 1

April 21, 2014 - We had an orientation which is basically about the survival tips, Do’s and Don’ts in the laboratory and then we had groupings (we were only two in the group). After that, we also had this free lunch sponsored by the Condensed Matter Physics Laboratory and then a laboratory tour. We (Group 1) had a discussion with our group mentor. She gave us the calendar of activities for our whole training. Our group will be on the Sample Preparation (Week 1), AC Susceptibility (Week 2), Transport (Week 3), ZnO (Week 4), Atomic Force Microscopy (Week 5). For our daily activities, we will be solving three (3) mathematical physics problems at 8:00AM – 10:00AM. Mondays at 1:00-3:00PM will be Statistics, Programming and Electronics (alternating per week). Then 4:00-5:00PM daily will be our classes for X-ray Diffraction (XRD) programming through Excel.

We were assigned to have a research on stoichiometry, solid state reaction, phase diagrams, heat treatments (sintering, calcination, oxygenation, annealing, quenching, RTA (rapid thermal annealing), and AC susceptibility.

Stoichiometry was used to determining the nature of the rate-controlling process from the mathematical analysis of the reaction kinetics and by investigating how the reaction conditions affect the mechanisms of a reaction.

Different processes of heat treatments:

Sintering is when a powdered metal product turned into a pellet (or a suitably shaped die or container to obtain a self-supporting) is heated in a protective gas atmosphere which bonding occurs between the metal particles.

Calcination is a process of heating a materials without melting, to drive off the material's volatile components.

Oxygenation is simply to combine something with oxygen

Annealing is a process by which glass and certain metals and alloys are rendered less brittle and more resistant to fracture which minimizes internal defects in the atomic structure of the material and leaves it free from internal stresses that might otherwise be present because of prior processing steps.

Quenching is to cool hot metal by plunging it into cold water or other liquids.


April 22, 2014 -  Our group was assigned in the Sample Preparation Laboratory but before any actual work, the Laboratory members assigned us to balance the equation having a product of 5 grams GdBa_(2-x)MnxCuO_(7-δ). After getting its stoichiometric mass, we were then taught on how to weigh its reactants and also on calibrating the weighing scale. After weighing the reactants, we were homogenizing and grinding samples. It took us time to homogenize and grind it. For 5 grams of product, grinding should be 1 hour, excluding the homogenizing process. After grinding, a laboratory member introduced to us sonication of apparatus and compression of our sample to a pellet. After our laboratory works, we went to the orientation of XRD. (We will be using Microsoft Excel's Visual Basics for programming XRD.) After the orientation, we went back to our respective laboratory and then went to furnace room. Our sample underwent its first sintering in a chamber of 900°C for 24 hours. We then had a reading on the introduction of crystallography with our station manager. It took us an hour of reading.


April 23, 2014 - We continued answering the problem set of previously assigned numbers. At 10:00AM-12:00PM, we went to the Yellow room to observe the Photo lithography processing. There were numerous of apparatus which are white light sensitive (white light being a resultant of superposition of all wavelengths from 400 to 800 nm of the visible spectrum), hence making it a reason to place them in the Yellow room (around 565 - 590 nm), as compared to broader spectrum of white light which may induce noise. After that, we went on for a meeting for our proposal which will be held on Friday (April 25, 2014). We agreed to have a proposed topic about the organic superconductor. We then had a discussion about THz Spectroscopy of Superconductors.


April 24, 2014 – We weighed another set of reactants which should have a product YBCO and homogenized it and then ground it into fine particles. For our XRD classes, we were taught about the basics of Visual Basics. Then at 5:00-7:00PM, the reading for THz Spectroscopy of Superconductors was continued and also the meeting for the proposal reporting was resumed, our mentor cannot make it with us, so there were three people who helped us for the proposal. It was quite difficult for us to have no mentor because we had no idea about what we should do. At least other laboratory members were quite helpful and cheerful.


April 25, 2014 – We finally came up to a topic (actually my groupmate got good idea on it. hehe): Analysis of the crystal lattice of doped Cs₃C₆₀. We were assigned as the third presenter for the first proposal reporting. We were really unprepared because we lack guidance from our mentor.


WEEK 2

April 28, 2014 – Every Mondays at 10:00AM to 12:00PM will be our free time. So while I have this free time, I was searching for another topic for our thesis and had the opportunity to visit some social networking sites. I was a bit confused on what topic we should take up as our thesis because I really had a very small knowledge about thesis proposal especially in relation to superconductivity matters. After lunch, we had our Statistics class by Myles Allen Zosa (at 1:00PM to 3:00PM). He discussed the t-test, doing one or two sample t-test, f-test, ANOVA, least square regression, and coefficient of determination. After having an hour of break, we went on having a class on XRD from 4:00 to 6:00PM. At 6:00 to 7:30 was the seminar by the master students. There were 3 who reported their progresses.

April 29, 2014 – On solving mathematical physics problems, we used the Tipler’s book (Physics for Scientists and Engineers, 5th Edition) after some consecutive days of using Arfken’s Mathematical Methods for Physicists, 6th Edition. Then we proceeded to our respective assigned laboratories after finishing the problems. We were assigned to be on the AC Susceptibility laboratory and had some few discussions. The one who discussed to us was also a junior (4th year undergraduate, since they have five years to accomplish their degree) of N.I.P. There were further discussions on its parts and functions such as Helium Compressor, Vacuum Chamber, Rotary Pump, Temperature Controller, Function generator, Lock-in Amplifier, Voltmeters and Computer, and Labview Interface. They also discussed what a superconductor is, that is, a zero resistive material and perfectly diamagnetic. The purpose why we should be learning in the AC Susceptibility laboratory is to identify the magnetic properties of the sample and its magnetic susceptibility.

 
April 30, 2014 – Our group at AC Susceptibility were discussing about the difference why it is called AC and why not DC. Furthermore, there were discussions that are related to Electrodynamics. We can’t work directly on the AC Susceptibility apparatus because its Helium Compressor was damaged. So to consume the time, we were processing data on SigmaPlot. It was the result of the YBCO with different amplitude voltages. Our main objective is to graph its out-phase (imaginary) and in-phase (real part) of the data. However, because of time constraints, it became the group’s homework. On our XRD class, we were assigned to look for the Scattering factors on each element of the Periodic Table. Concerning our thesis proposal, our mentor said via Gmail that we just have to pursue what we have started. But, we have not seen her this week. We really want to change our proposal because of its difficulty level. Our proxy-mentor is encouraging us to change the topic. She said that if the original mentor would really want us to continue our first proposal, then she should always be there to guide us and assign some readings.

 
May 1, 2014 – Labor Day! But I was just making my assignment.
 
May 2, 2014 – As usual, we were solving problems from Tipler’s Physics for Scientists and Engineers, 5th Edition every 8:00-10:00AM. At 10:00-12:00, they have discussed the basics and shown to us what were experienced in the cold head of the Rotary pump via Oscilloscope. We were also assigned to fix some circuit in bread board and checked the Voltage Inductance and the Impedance of the coils (Primary, Secondary A and Secondary B) of the cold head. We gathered what had appeared on the data to Excel which consumed most of our time. We were then assigned to report the results on Tuesday (May 6, 2014). On our XRD session, we have utilized the results on our assignment about the atomic scattering factors.


WEEK 3

May 5, 2014 – Our subject in the afternoon was about the Programming of the software LabView (1:00PM – 3:00PM). I really appreciate it as a whole because it is so colorful! I am really excited to go home and study these programming stuffs that I have learned here such as Microsoft Visual Basic for Application (Programming in Excel), LabView, and SigmaPlot but it really takes a lot of time and effort to go and study alone. It can help us make a graphing software of Current-Voltage curve. The problem was that it is so hard for me to go with the flow of the discussion because it is way too fast. At 5:00-8:45PM, we joined the seminar for the Master students and Sir Sarmago was there giving comments and asking questions. His voice caused Goosebumps on my skin. After the reporting, he introduced himself to us and was asking for our names. He also invited us for a dinner at Don-Day’s restaurant. We just need to prepare 300Php maximum. We have been dismissed and then we were having a discussion with our mentor Mayrene Uy concerning the Thesis Proposal for the next day (May 6, 2014) and informing her about the presentation for our seminar on (May 10, 2014).

May 6, 2014 – At 10:00-12:00PM, we had our orientation with Glaiza Blanca-Ocampo. She was discussing about the Transport Laboratory and its objective. Our group was late in reporting to the laboratory because we were doing/submitting our assignment for our AC Susceptibility results. Also, we were informed that there will be no laboratory meetings at that time. It seems like she is upset because we made her wait. Honestly, we did not know that she was waiting because she was just taking over the Station Manager because he can’t make it there. After the orientation, I had the opportunity to continue our assignment in AC Susceptibility and prepare for the Thesis Proposal later on 3PM. I was required to solve for the Secondary Coil A of the Mutual Inductance Bridge with Peak to Peak Voltages of 2V and 5V. From 3PM, there are 3 high school interns who reported their investigatory project and 5 groups for the college. Our group is the 4^th presenter and my part is the introduction of our revised thesis proposal: Fabrication and characterization of superconducting fullerene. We ended up until 7PM after Boss (Sir Sarmago) has given us some inspiring thoughts.

May 7, 2014 – Our group was assigned to read the books: Electrical Characterization of Thin Films and Electrical Characterization of GaAs Materials and devices up until 12PM. After reading, I continued my assignment in AC Susceptibility and submitted it after our XRD classes. We grabbed the opportunity to have a discussion with our mentor for our seminar this Saturday. She was assigning me to look for the intercalation journal topics which is related to to our thesis proposal and then we must be preparing a draft for our Powerpoint presentation. At 2PM, we were putting on contacts on a sample by soldering Indium and gold wires. They were not using Lead soldering wires because at 40W, the soldered Lead would become solid balls at an instantaneous time, compared with Indium. They were also using gold because its conductivity is high. Some may be using silver, but they preferably use gold because it is much better. In putting contacts, there are two types of positioning, one is van der Pau, and the other is Four-point probe. We were taught on how to put contacts with these different positions. On our XRD classes, we were assigned to program the crystallinity of Rock salt with the given details. After that, we were having a reading on Aldwin’s (my group mate) journal.

May 8, 2014 – At 10:00-12:00PM, we were taught on how to use the Transport Machine for the IV Measurement by checking the sample’s Hall and Resistivity. The materials I have noted were the Current source, Multi-meter, Circuit Breaker and Temperature Controller. We were connecting the sample on a PCB using Silver paste, but firstly, the silver was melted with Butyl Acetate. But it seems that the program was error. So the programmers (also Immersionists who came from NIP) repaired the program. While waiting, I was trying to make an outline-draft for the seminar. Here was my planned outline:

1.       Define Fullerenes

2.       Present nanotubes and nanowhiskers

3.       Their structure

4.       What would be its intercalation method if alkali metals are doped

5.       What could be the results of the different alkalis under SEM and XRD?

6.       Summary.

After making this draft, the program was finally fixed at 3:15PM. We were checking the Resistivity and Hall Coefficient of YBCO sample. The sample’s assigned van der Pau positioning is

The Red, Violet, Yellow and Green are the gold wires, and it is connected to the sample via Soldered Indium. In checking the Resistivity, the following patterns are used: 2134, 1234, 3241, 2341, 4312, 3412, 1423, and 4123. The order of these number means we will be connecting it to the +I,-I,+V,-V of the multi-meters. After checking the Resistivity, we were checking its Hall. Here are the methods:

1.       Open the main faucet of the water and then the faucet for the magnet.

2.       Open the Magnet Power Supply

a.       Press Function Menu

b.       Press Ramp Status

c.        Change from 0 to 42.083 A to convert it to +2 Tesla

d.       And then Enter

e.       Turn on the Ramp Status

f.         And then press Normal display.

We were then connecting the multi-meters to 3142, 1342, 4213, and 2413 for the Hall. Procedure was repeated except that it is now at -2 Tesla.

                After the laboratory, we had no class in XRD and went to Don-day’s at 6-9PM with Sir Sarmago’s car. It’s an Eat-all-you-can restaurant with Korean culture such as cooking meat at the table.

May 9, 2014 – For our laboratory activity, we were getting the slope by graphing the results of the last day’s result (IV Measurement). The value of the slope is the Resistance. After graphing, we put on the data to the given programmed Excel to get the value of Hall coefficient. After graphing, I have shown my draft of Powerpoint presentation to our mentor and made some revisions from her advices. There were so many questions asked for my preparation during the Seminar. I was so glad that at least, she checked our progress despite of her time constraints. After meeting with her we were rerunning another sample through the transport machine. The sample was 2212 pure, with the thickness of 1.70 mm. We also had a review on how to read using Vernier Caliper.

May 10, 2014 – I was the last presenter of the Seminar and it seems like people had some information overload. There was not much of questions concerning my chosen journal. The title of my presentation is Synthesis of Alkali-metal-doped Fullerene nanotubes using vapour evaporation Method. I was basing on the journal Synthesis of alkali-metal-doped C₆₀ nanotubes (2011). There were 5 reporters on the morning and then 6 reporters in the afternoon. Sir Sarmago was there during morning but not in the afternoon. These are the key points I got from him:

1.       As a seminar speaker, we should be audience centralized, we need to get the attention of the audience.

2.       Also, we need to get the background of the journal, that’s why it is good for us to have a lot of seminar because it would make us scientifically intelligent.

3.       And lastly, as a listener to the seminar, we should not let the speaker waste our time

After the seminar, we went home and took some rest and shopped at Quezon City Circle as much as we need.

WEEK 4

May 12, 2014 – We had no activity during our 10:00-12:00PM, then I grabbed my opportunity to search for methods on how to dope potassium with Buckminsterfullerene. For 1:00-3:00PM, we were having our class on Electronics. Ma’am Bess was discussing about the advantage of having knowledge in Electronics, about Amplifiers and the derivation of the formulae given the situation. After that, we had another free time from 3:00-6:00PM (we had no class in XRD) but I only focused on making a draft methodology for our proposal tomorrow at 3:00PM. Here is the plan I had: 1.) Use vapor evaporation to dope potassium. 2.) Further explore the effect of various temperatures on the doping concentration for potassium. 3.) Characterization using Raman spectroscopy. I have planned to use what I have studied on our previous seminar. Honestly from the very beginning, I was really hoping that my group mate is just someone I used to know in MSU-IIT because it is really so hard for me to deal with him right now. It seems like a hindrance to my joy of learning in CMPL because I feel like I’m so limited in terms of language expression. He may be a gentleman, but it’s more fun if I already knew my group mate. I hope that at some time during this OJT, we would feel comfortable in the field of work.

                From 6:30-8:35, there was a Mock defence of the two laboratory members in CMPL. The spectators were correcting them without bias and were encouraging to keep their work up. I was greatly encouraged to do what I want for the better especially in the field of research because maybe they can understand what I am right now. The meeting was then adjourn on 8:35.

May 13, 2014 – During our 10:00-12:00PM session, supposedly we are now assigned to our new laboratory station: ZnO. However, we had no orientation. So I just continued on making my report for the proposal this afternoon, 3PM. There was not much of an activity this day, we only had 8:00-10:00AM for solving Mathematical problems, 2-4:00PM for a defense of a master in Physics, Joey Kim Soriano, whose topic is Decontamination of fungi infested oil-on-canvas paintings via the microwave atmospheric plasma pencil (MAPP). At 4:15PM, until 6:00PM was our proposal presentation. Our group presented third and reported our updates about the alkali-metal-doped with fullerene because Cesium is way too hard as a dopant because at some time, it becomes unstable. Therefore, we have changed the dopant to potassium, whose critical temperature is 20K. After reporting, I was writing about what I have learned, which I should really do. 1. Write the script for the report. 2. Always base your script on the powerpoint presentation. 3. Be sure to look for the application. 4. I should know what I really want to study. It suddenly pops to my mind, and I think I need to write it so that I could remember these lessons learned. After that, we had our meeting with Kuya Dustin from 6:05PM about our Farewell party for the high school interns, Arb and I was assigned for the certificates and Sash for the Kalabasa Awards.

May 14, 2014 – There was not much of an activity this day. At 10:37, we had an orientation of ZnO laboratory station with Ate Vida. I really wonder why ZnO is included in the Supercon Group. As I was asking it, she said that it is Boss’s personal decision why he needed it in the Group.

    ZnO is a white powder, insoluble in water, 3.34 eV band gap and has photoluminescence properties. It is also transparent due to its band gap, however, it is tunable. It is also biocompatible, easy to fabricate and useable. There was this question Ate Vida asked, “Why is it necessary to refabricate ZnO, when you already have a pure ZnO?” The answer states that it can actually be shaped into different atomic structures which is necessary for the fabrication for application. There are many ways in fabricating it – carbothermal method, hydrothermal/solvothermal, radio frequency sputtering, pulsed laser deposition, and thermal evaporation. Our orientation ended up until 11:15AM. At 1:50PM, we were assigned to look for the Gwyddion installer. After installing it to our laptops, we had another free time. I was downloading a lot of journals because our seniors in BS-Physics have recommended us that we should download journals for our upcoming seminars. At 3:35PM, there was a brief discussion which is related to Ate Jam’s sample. She was using the Carbothermal reduction route for her study. She was furthermore discussing about the mechanism of the Carbothermal Furnace and how it works, the defects and the disadvantages. She also discussed the orientations of the ZnO – A-orientation and the C-orientation. She described to us the difference between the two especially in the physical aspect. A-oriented is flat, ribbon-like structure, whereas c-oriented is rounded like a wire. After a brief discussion, she gave us a task, which was to separate the a-oriented and the c-oriented ZnO. We used the transmitted microscope (which has its own synthetic light below) to enlarge the sample and check its orientation. We ended up until 6:00PM. After that, we went out and had a discussion of our preparation for the Farewell Party for High School interns. We have submitted the Kalabasa Awards. Here are the list: The Biggest Loser, Tirador ng Mortar, Dala ka FOODS, Punta ka NIP, De-caffe, and Maniniyot (Tagalog). We have also planned about the games and program. Our master of ceremony would be Ate Maye La Madrid with an NIP immersionist, Angelo and our game master is Ate Lady Jabber.

May 15, 2014 – At 10:45, Ate Verdad was discussing about the difference between the hydrothermal and carbothermal methods to get ZnO. Basically, the carbothermal method needs an addition of activated carbon and its temperature is high. Whereas for the hydrothermal method, the temperature is low (95°C) and the reactant is Zinc Acetate Dihydrate. Here is the reaction using the hydrothermal method to have a product of ZnO:

Zn(CH₃COO)₂ · 2H₂O_(aq) ßà Zn²⁺_(aq) + 2CH₃COO-_(aq) + 2H₂O_(l)

C₆H₁₂N_4(aq) + 6H₂O_(l) ßà 4NH_3(aq) + 6HCHO_(aq)

NH_3(aq) + H₂O_(l) ßà NH⁴⁺_(aq) + OH^-_(aq)

Zn²⁺ _(aq) + 4NH_3(aq) ßà [Zn(NH₃)₄]²⁺_(aq)

Zn²⁺_(aq) + 2OH^-_(aq) ßà Zn(OH)_2(l)

Zn(OH)_2(l) ßà ZnO_(s) + H₂O_(l)

After showing this chain of reaction, we were converting the molarity of the sample (in grams) needed for the experiment. There should be ten millimolar (10mM) of powder and 40mL solution needed to produce 0.087804 g of Zn Acetate. After that discussion, at 11:15AM, Kuya Nannie taught us on how to cut a substrate until 11:30AM (for my case). The procedure we did was this:

1.       Measure the substrate 0.5 x 0.5 cm.

2.       On the rough side of the substrate, make a slight strip measuring 0.5cm using cutter (substrate)

3.       Flip the substrate and then press where the opposite side has a strip of cutter.

4.       The substrate will automatically get cut in equal size because of its lattice.

At 11:30-1:15PM, we went to some mall near the Katipunan to buy materials (stationary paper for P14.50, 6m of blue ribbon for P7/meter) for the Farewell party for the highschool students and then went to some “Lutong Bahay” restaurant. After that, Kuya Nannie assigned us to read about the letter (Mg-doped ZnO hydrothermal samples) sent to him by someone who was working on his sample. The message contains that there was a 323 nm adsorption edge, when the usual adsorption should be 380 nm. Maybe the reason was the thick glass substrate. Then the letter recommended to use cover slip instead of slide. Attached with the letter was the procedure in cleaning the cover slips. Here is the method which I written-copied:

1.       Mix dH2O (deionized water) and a small amount of liquid detergent.

2.       Mix the detergent solution with hot purified water. The amount of hot water should be greater than that of the detergent solution.

3.       Mount the cover slip in the plastic tweezers using masking tape. Make sure that the cover slip will not fall during the subsequent procedures.

4.       Soak the slip into the solution. Be careful not to let the cover slip touch the sides/bottom of the beaker

5.       Sonicate for 15 minutes.

6.       Remove slip and rinse with tap water.

7.       Rinse cover slip with dH2O five times.

8.       Pour ethanol into the solution. Be careful not to let the cover slip touch the sides/bottom of the beaker.

9.       Sonicate for 15 minutes.

10.   Remove slip and rinse with ethanol.

11.   Remove cover slip from the tweezers and store in ethanol prior to deposition.

Supposedly we ended up until 3:30 PM, but by 5:20PM, Ate Vida came and we were made to sonicate for the materials needed for her sample. We were then assigned to grind her sintered sample ZnO. Its color was yellow. And I have not written the reason why. We really need to shop to the SM North Edsa for the tokens and sash that will be given tomorrow for the Farewell Party. I was so glad that Ate Jess helped me in making and buying materials for the sash.

May 16, 2014 – At 11:15AM, we went to the Scanning Electron Microscope (SEM) room (located with the same area of Yellow Room). We were required to wear something on our shoes before entering the room for cleanliness’ purposes. We were observing their simulated data. At 12:05PM, we were asked to stop all works because Bossing said that we will have a free lunch at Room 310 as an initiation for the Farewell party for high school interns. After eating, we went to join a program for the closing remarks of the Philippine Science High School (PSHS) Internship. I have realized that there were so many interns within the NIP, laboratories which include Instrumentation, Photonic, Theory, and others. There was also a distribution of certificates and souvenir for them. At 6:30PM, the program for the Farewell party of Superconductor Group was held at F209. First part of the program was the distribution of certificates and sash for the Kalabasa Awards. Next part was the games: Modified Singing Bee. After that was the giving of the tokens and messages for the interns. Then, we ate lots of pizza from Pizza Hut. Further, we took lots of pictures to make some memories with the interns. We even transferred to the lawn to take some. We really had a good night and bonding and vanity with the laboratory members and interns. J This is the second time to get to know more of them.

WEEK 5

May 19, 2014 – For our 10:00-6:00PM, we did nothing but to do some research for our incoming Fourth thesis proposal tomorrow. I was assigned to discuss about the characterization of potassium-doped fullerene. The figure at the right is the molecular structure of C60 fullerene. The characterizations to be used are: Raman spectroscopy, X-ray Diffraction pattern, ρ-T Measurement (Resistivity), AC Susceptibility. At 6:00-8:30PM, was the seminar of the Supercon group members. Sir Saaki discussed about the “High temperature superconductor Terahertz emitters: Fundamentals Physics and its Applications”, Ate Jam discussed about the “ZnCuO Dilute Magnetic Semiconductor and its applications in Spintronics, Kuya Jonalds for “New Approach: Sedimentation from 2212, CaCu2O3 and CuO precursors”, Kuya DC for his progress report. After that there was an announcement about the Thesis Defense of two undergraduate members: Ana Marie Geronimo (Ana) and Louisse Anne Fulgencio (Ate Lala). We adjourned 8:30PM.

May 20, 2014 – We had no classes for our 8:00-10:00AM session because there will be a thesis defense of Lala on 9:30AM-10:30AM. After that, for 12:30PM-1:40PM was Ana’s defense. I wrote my script for our thesis proposal later. Aldwin was assigned to discuss about the introduction and fabrication of K3C60. ¹After fabricating it, we need Raman spectroscopy to determine if the fabrication was successful. The pristine C60 spectrum has its sharp peak at around 1432 cm^-1, which is known as the pentagonal pinch mode. 

The sharpness of the bond tells us that the bonds are for the most very uniform in nature. When it is doped with potassium (K), there should be an expected distortion of Raman spectrum.

 ²After identifying its success in fabrication, there is a need for us to describe the crystal structure and orientation. So we need X-ray Diffraction pattern. Based from the study of Takeya (2005), the resulting XRD pattern of K3.3C60 has the resemblance of the pristine C60. There are specific peaks, the 111, 220, 331 and 222 which could possibly describe the fcc structure index. Same for our case, we need to identify K3C60’s structure index.

³Now, assuming that we already knew the structure of K3C60, we need to check the zero resistivity of the sample, hence, we need the ρ(T) Measurement. A sample having a very low resistivity indicates that a material readily allows the movement of electric charge. The figure below displays the measurement of the temperature dependence of the resistivity (measured under conditions of constant sample pressure). As you can see here, the resistivity of the K3C60 crystal abruptly drops at critical temperature of approximately 20K.

 ⁴Checking the sample’s superconductivity wouldn’t be complete without testing its magnetic property. From the study of Boebinger (2010), when there is no field applied, its critical temperature is approximately 20K. When some field is applied, there is an abrupt change of its X_ac.

                The first reporter was Arb and Ate Maye’s group to report. Next is our group. The advice for our group was that we should firstly consult the magneto-transport laboratory and AC susceptibility on how we should be able to identify its superconductivity. We should also change the color contrast of our powerpoint presentation and lastly, we need to specify more of our title report.

May 21, 2014 – We resumed our Solving mathematical problems for 8:00-10:00AM. After that, at 10:00-10:55, our group joined the meeting of Kuya Michael, Ate Bess, and Ate Jam concerning Kuya Nannie’s sample. Ate Jam told us that the Atomic Force Microscopy’s (AFM) limitation is to check the area only in 100μm x100μm. Kuya Nannie’s sample is 1x1cm ZnO. They were talking about some strategy on how to check the sample via AFM. After that, Ate Jam and then Kuya Cyrus discussed a brief overview of our task and gave some files for the AFM station. Kuya Cyrus also discussed the basic parts of the AFM: the cantilever (used for manipulation), feedback system and piezoelectric material. It can be used for 3D profiling, checking magnetism, and others. At 11:15PM, we were having an observation with Kuya Mike. He discussed that AFM comes from the family of Scanning Probe Microscope.
The needed parts of the AFM are: 

computer, scanner head, cantilever tip, piezoelectric tube, controller, microscope, vibraplane, and CCTV camera. The cantilever tip moves across the sample by either tapping or touching the surface. He also discussed the technique which involves the laser and photodiode. It is called the Beam-bounce technique. From the laser to photodiode (reflected through the back part of cantilever), results to some differential current. Then, the current will be sent to the feedback system.  The feedback’s system is to maintain the tip-sample distance. Then, the piezoelectric tube changes, causing the change of the cantilever’s pointing position due to vertical axis.

There are conditions which an AFM checks. The samples:

1. Should be clean and has no loose particles.
2. Should not be wet because there will be a capillarity effect to the cantilever tip. When the tip hits a wet surface, the liquid tends to flow up to the cantilever which could then give weight to the cantilever tip, which could result to changes in measurement
3. No biological sample or jellylike structure
4. No porous nor cluster of rods in the sample.

After that, we had a break at 11:50AM and resumed at 1:30PM.

The composition of the cantilever tip is silicon nitride. Kuya Mike taught us the steps to check the sample.

1. Tip installation.
2. Laser alignment
3. The sample must be put to a Sapphire Alumina substrate with medicinal tape. It is needed to avoid noise

There are different modes on checking the sample.

1. Contact mode – touches the sample
2.  Semicontact mode – There is a force oscillation/tapping
3. Non-contact mode – does not touch the surface

He also taught how the program works. There was a current fluctuation on 2:55PM, so the operation stopped and resumed at 3:30PM. While that happened, we were having a reading on the Fundamentals of AFM. After running some few sample, Ate Jam asked us about what we have learned as we were reading the E-book. There was a quote from her which I could not forget, “Believe in what your heart says”. It really sunk in my mind on how and when she said that quote. It really gave me courage to answer and trust in what my mind says. Although I often hear the quote many times, but the situation was way too unique to remember.

May 22, 2014 – We were having a review on what we have learned yesterday. We continued on running some samples to be sent to Osaka, Japan. On 4:00-5:45, we had a reading on Aldwin’s chosen journal for his seminar on Saturday (May 24, 2014). Ate Mayrene said, “Always assume that you’re the expert”. She said that we will be having a reading on 10:00AM tomorrow for my seminar. The journal topic was about the encapsulation of fullerene in a carbon nanotube.

May 23, 2014 – After having a session on solving mathematical problems, I requested Kuya Mike that we will be working for our seminar tomorrow. However, Ate Mayrene did not arrive at 10:00 AM. We never had a reading for my journal this day. Since she did not arrive, I changed my topic and chose the easier ones, something that is time efficient. I saw her in a rush afternoon and I told her that I changed my topic because the previous journal topic needs quite a lot of analysis. And she agreed. After that, I was making my powerpoint presentation and focused on the methodology.

May 24, 2014 – Seminar day. I was the third ones to present our journal. The title was Controllable preparation of fullerene nanotubes (2014) by Bingzhe Wang, Xin Gao, and Guangzhe Piao. I firstly presented what a fullerene nanotube is. It is a closed cage of symmetrically arranged carbon atoms.

In the image, assume that you cut the C60 into half and then you add 10 carbon atoms in between the gap. You could form C70 atoms. If we repeatedly do this, we could form C1,000,000 such that it could form a carbon nanotube. The difference is that, as a fullerene, it is an enclosed carbon nanotube. It is a hollow, elongated like a fiber and inherits the perfection of atomic arrangement made famous by its predecessor, the buckyballs. It contains only hexagonal and pentagonal faces. There are different methods in forming fullerene nanotubes: Solution Evaporation Method, Template technique, Surfactant-assisted method, Volatile diffusion method and liquid-liquid interfacial precipitation (LLIP) method. The study focused on the LLIP method. What I added was to compare the results of the previous study which uses the LLIP method. The objectives herewith is to: examine the effect of the ultrasounded treatment on the tube-content determination and the producibility of fullerene nanotubes (FNT) for industrial production, shorten the growth induction period of the FNTs for industrial production and compare the results of the previous study using LLIP. Previously, the total time to get fullerene nanotube is 2 weeks and 4 hours. But by this new study, they were adding an ultrasound treatment which it costs them to waste only 12 hours and 15 minutes.  There were few questions asked (which makes me think that they were interested, because they were talking in groups J), but I have realized that I could hardly express my thoughts and would be so nervous about their curiosity. It makes me think that I have not successfully answered them. It makes me feel a bit upset. But I would just charge it to experience. At least, I should be more knowledgeable about this things, moreover, I should know how to communicate, then "Believe in what your heart says”.