Kevin McLaughlin - NanoJapan 2013
Northern Arizona University
Anticipated Graduation: May 2017
NJ Research Lab: Ochiai-Aoki Lab, Chiba University
NJ Research Project:Magnetic Force Microscopy of the Magnetic Domains in Co Y-branch Structures
The NanoJapan program provides research experience for students primarily in physics and engineering prior to their own career explorations. The international aspect of this program allows students to become accustomed to the growing interconnectedness of these disciplines within the world. These important aspects of the NanoJapan program are a couple of the reasons I chose to apply. In addition to these aspects, I sought the cultural immersion in Japan. I am already planning to participate in an internship in Japan (separate from the NanoJapan program) and therefore this program is profoundly beneficial to me. Considering I am a physics and mathematics major as well as a Japanese minor, the NanoJapan program is largely beneficial to me since it has an emphasis in physics along with Japanese courses and immersion. My excitement in the program extends to its cultural immersion, language speaking, and overall research focus. I am eager to engage in research that I may conduct in the future and gain a valuable understanding of the Japanese language and culture. There is no doubt that the trip itself (since I’ve never been outside of the US before) we be tremendous and eye-opening.
My goals for this summer are to:
My initial impression of Tokyo was met with shock and excitement. I really enjoyed seeing the amount of green in Japan; I also was stunned by the cleanliness of the city (despite the lack of trashcans). An example of the differences between what I anticipated and what I witnessed upon arriving in Japan was the buildings. I never imagined the various shapes that characterize the buildings here in Tokyo. In addition, I was quite shocked by the large similarities that Tokyo has with typical US cities. In general, everything was a lot smaller or shorter than things in the US, which I assumed it would be. The evening with the KIP students was wonderful. The topics were thought provoking and interesting. Afterwards, a group of us joined some of the KIP students for dinner, in which we went to two different restaurants over a two hour period. I was surprised that many of the Japanese students felt that silence was not golden.
When people use public transportation, such as trains and the subway, they do not talk on their cell phones. Also, there is reserved seating for people who are old, injured, pregnant, or have children with them. People tend to give up their seat for older people to sit down. In addition, it appears to be common for people to stand up and walk towards the door prior to the opening of the door at the station. My usage of the train and subway system in Japan has been miniscule, so I am unsure as to how this general behavior changes with time; however, the closer to closing, the less people there are. Often people will listen to Ipods/mp3 players while using public transportation. People seem to be on their phone most of the time, whether texting or checking something. Sometimes there are conversations being held, which tend to be quieter than ours. There is virtually no “messing” with people who are asleep and people do not really push past one another. I have actually barely used public transportation in the United States. I would have to say that what I noticed in the Japanese public transportation system would be a cultural result; however, standing on the left side of the escalator, as opposed to the middle, is more practical.
In Minami Sanriku, I saw a lot of rubble, including the half standing buildings composed of steel that were bent in various directions. Also, there were bridges that were devastated by the tsunami. The trees that had been hit by the tsunami had all died as a result of the salt. It was especially difficult to imagine the city that was there before the tsunami hit. All I could see, aside from some debris, was vacant land; there was hardly anything to see. I hardly knew anything regarding what occurred in Minami Sanriku and I think even if I had known more about it, I still would have felt shocked. I did not know that the United States aided the people of Minami Sanriku, or that the people were so thankful for it. From what I heard and saw, the Japanese people are working hard to rebuild their own city, while living in temporary housing. The government aid seems to be insignificant in the area, which appears to be the reason the place is still largely underdeveloped despite having been a little over two years since the tsunami hit Minami Sanriku. I feel that 3/11 was very impactful on the Japanese people; however, the rate of recovery does not reflect that. I honestly have no suggestions as to how the US, or the American people in general, can help Minami Sanriku. The people of Minami Sanriku do not appear to be giving up and the area now has the ability to redesign and improve upon the previous city more easily (start again as oppose to trying modify).
I really enjoyed the various discussions with the KIPP students. The different discussions that occurred prior to the Minami Sanriku trip were well planned out and were quite enjoyable. I would have to say that I enjoyed the conversations we had during the Minami Sanriku trip more so than the planned conversations. During these conversations I was able to learn more about them personally. In addition, I was able to speak, at least to the best of my ability in Japanese. Speaking with the KIPP students improved my Japanese language skills by learning new terms and served as a great time to practice. Also, it appeared to make them, at least to some degree, more comfortable.
My first day at the Chiba University lab was both slow and awkward. I had to try on the clean suit and shoes to find out that neither of them fit; as a result Aoki-sensei had to order a larger clean suit. I was not allowed to enter the clean room until I received the clean suit, which took about a week to arrive. This dilemma was the major reason why the first day was slow.
One by one, as they came into the office, my lab-mates introduced themselves in English. Unfortunately, they are not all that good at speaking English and by extension are not comfortable to do so. These introductions were very awkward, and to be honest I think I was less nervous than they were regarding the self-introductions. My mentor is Masahiro Matsunaga and he is a second year Masters student. He speaks mildly good English and despite this slight language barrier we communicate quite well (with the help of Google translate). He is definitely an interesting person to be around. As the days progress the other lab members try to talk to me more and more often and I currently have good relationships with the other undergraduate students: Naoto, Kiyota, Mukasa, and Takeda as well as the two Chinese Doctor students: Kou and Gi (which are their Japanese names). The people in my lab can speak partial English often it takes three or four of them to formulate a sentence. This difficulty speaking English, coupled with my insufficient Japanese language skills, results in long conversations without my inclusion. I live in a dorm at Chiba University International House. My dorm room is single occupancy and very small, which I am unaccustomed to; however, it is a very nice place to live. It takes me about thirty minutes to walk from my dorm room to my host lab (needless to say I am getting a lot of exercise). One interesting thing is that I have learned to play Shogi, which is the Japanese equivalent of Chess; I find it to be more difficult.
Currently I am undergoing training to be able to use the SPM system to analyze the topographical features of a sample and later I will begin training on how to use the SPM system for MFM. I just began training on Friday due to the issues regarding the clean suit. I am still undergoing training on the SPM system and will be undergoing MFM training soon; since we are essentially a week behind, we have not formally established anything regarding my research. All I know is that it includes using MFM to analyze the nano-magnet samples that they received from Professor Bird.
I do not feel as though I have had a cultural incident or at the very least I am not aware of it. I tend to ask questions if I feel that something might have a cultural stigma attached to it. As far as communicating with the people of Japan in general, it can be quite difficult at times. I have learned from some of my lab-mates that I talk too quickly at times (most of the time actually) and I tend to use a lot of big words that they are unfamiliar with. Also, sometimes it is difficult for them to relay information to me because of their limitations speaking English. Often three or four of them will communicate in Japanese with each one trying to explain it in English more clearly. Their inability to speak English, coupled with my larger lack of Japanese proficiency, is rather troublesome, because I tend to ask a lot of questions; even when they understand the question I am asking, it seems to be difficult for them to answer. I am not sure whether this difficulty stems from the questions themselves or trying to answer them. The language barrier results in both sides resorting to other people, or Google translate, for assistance. In addition, I am often a bystander when discussing the results of our experiment or when deciding the next step; it is typical for me to be given the information after it has been decided. Despite these difficulties we are able to communicate fairly well.
Research Update: Our research on the magnetic domains on Y-branch samples after imposing an external magnetic field began with an observation of each of the orthogonal positions relative to the Y-branch. As of recently, my mentor and I have finished these observations of two of the four samples with the use of MFM. We have had to rescan each sample multiple times at various times in order to get a clean, good quality image. The major complication thus far in regards to obtaining good data is noise. This noise in the scanned images results in blurring, shifting, and/or covering of the image. In the last week this appearance of noise has been more apparent. Typically we try to rescan the sample using the same conditions in order to maintain a commonality amongst the samples; however, on occasion we have had to reduce the scan speed and/or increase the interleave height (the distance between the first and second scan). Raising the interleave height reduces the clarity of the image, but it can reduce the amount of noise. We have not yet determined what we are going to do next. One of the possibilities is to repeat these scans for samples three and four; another possibility is to begin experimenting with different combinations of imposed magnetic fields. We can also scan the same sample with the opposite pole of the magnet. Those are some of the current possibilities being discussed, however, there are more possibilities that I did not list.
The questions that are laid out this week seem quite hard, especially since I notice only the human behavior that is common amongst all people. Therefore, I see my lab-mates and professors behaving with the same intention as human behavior would dictate. The professors aid in guiding the students, while in response the students act in a cordial manner. The goal of this style of communication is a more beneficial environment for research and learning. This behavior is what I observe, not the more trivial distinctions. With that being said, I have observed a minute difference as a result of the hierarchy that exists amid the Japanese laboratory setting. This difference includes the usage of different honorifics such as: kun, san, and sensei, but the usage of honorifics is still used as a manner of respect, which is a common behavior amongst all people in such a setting. Furthermore, the doctor, master, and undergraduate students are all separated; however, it does not prohibit intercommunication, nor does it foster any class distinction. It is actually a product of minimal space. As professor Kono mentioned, the labs in Japan utilize various slippers depending on the room you are in; though this behavior primarily stems from traditional customs, there is a practical reason for this behavior – to minimize contamination.
In general, it appears that people tend to do want they feel is necessary. In this particular case, people often stay late (although there is no defined start and end date for the lab) and do not sleep much as a result. Also, focusing on the details tends to be important when conducting research in the lab. In addition, achieving desired, or at least good, results is a high priority and valued, thus the research is often redone until good data is acquired. The importance, or value, of team collaboration is apparent, but it is equally as important for an individual to be able to conduct the experiment. As a result the group is composed of a combination of people who are specialized in that area, thus resulting in distinct groups of researchers composed of similar researchers. Unfortunately, I have not conducted research in the US; therefore, I am unable to compare the Japanese and American lab characteristics at this time.
Research Update: This week we observed the magnetic domain structure of the sample while in a magnetic-field. So far the results indicate a strictly polarized effect with virtually no deviations. We intend to observe each of the states when the sample has an orientation of 0, 45, 90, 135, 180, 225, 270, and 315 degrees in relation to the initial location of the sample (with the Y-branches facing downward) and the magnets. We have completed 0, 90, and 180 degrees thus far. Also, we are looking into designing a solenoid-based mechanism that will create a magnetic field, which can be manipulated by changing the voltage, and by extension the current. With this device, we hope to observe the 50mT to 100mT range in order to observe some of the intermediate effects within the magnetic domain structure. We have also calculated the magnetic field of the magnetic stage to be about 46mT. We have had some difficulty trying to develop the solenoid device with an effective magnetic field; therefore, we plan to utilize a cut circular core rather than two rectangular cores.
I would have to say that my biggest accomplishment thus far is understanding the katakana. I have been able to read what it says; however, it has been difficult for me to translate what it means (despite them being predominantly English words). I feel that my continual effort to read everything I see has not only helped with this, but has also aided in general reading practice. As a result I can recognize the hiragana, katakana, and even some kanji more quickly.
The most difficult challenge for up to this point has been, in part, the language barrier. Typically, my mentor and professor will hold an entire conversations deciding what we should do to solve a problem. During these conversation I sit there silently while they continue to converse in Japanese. After they have decided, my professor gives me half a summary, which often result me later asking my mentor for more information. The reason this is a challenge for me is because I have no input at all in my research. Not only do I have ideas that I would like to put forth, but also my own concerns regarding the proposed plan. I do not attempt to interject because I do not know what is going on at the time and therefore I do not know the appropriate times to interject. Also, I feel that it would be rude to leave the situation; however, there is no reason for me to stay – especially when I could be doing something productive while they talk.
Research Update: This week’s research has consisted of finishing the observations of sample one and sample in a magnetic field of approximately 46mT. We finished the samples at relative orientations of 0, 45, 90, 135, 1180, 225, 270, and 315 degrees. We observed strictly polarized domain structures in both of the samples, thus indicating a dominant magnetic field. Currently, we are working on obtaining the MFM images for the sample after being exposed to the magnetic field with an orientation of 30, 45, and 60 degrees for 10 seconds and then scan without further magnetization. Also, we are having some difficulty developing an apparatus that will allow us to observe a lower range of magnetic field that ranges from 0mT to about 30mT. Some of our ideas consist of the utilization of one or more solenoids (both ring and bar shape, and with different cores) and a movable magnet. Some of the complications of designing/ buying a suitable apparatus is the limitation of size, because we must be able to put it in the SPM without it interfering with the MFM tip; also the outward space of the stage, which holds the sample, is limited. The reason we want to scan the samples in a field with a lower magnitude is to potentially observe the domain structure that is related to the peaks in a graph derived from a simulator. We also intend to rescan several of the images due to their average quality. We are continuously waiting for new supplies, because MFM is new to this lab; however, each wait is generally quite short.
The Mid-Program Meeting was very enjoyable. Okinawa is in many ways quite different from the rest of Japan. Although it was rather hot and humid (the latter of which I am not use to), the activities we engaged in (i.e. snorkeling, cultural outings, lab tours, etc.) were quite interesting. Also, meeting again with the other NanoJapan students was wonderful, since it had been just over a month since our three week stay in Tokyo together. To sum it up, it was a nice break to act “American” again rather than the continual censoring we must do in our labs. I think that holding the Mid-Program Meeting in Okinawa should be continued mainly because it has a unique culture. In addition, English is more prevalent in Okinawa which serves as a relief for the continual onslaught of Japanese, which becomes fatiguing. In a sense, the Mid-Program Meeting, in Okinawa, revitalized my ambition for my lab work and my additional Japanese studies. OIST was a beautiful place and very interesting to see, and I am certainly interested in attending. I chose to compare the OIST program structure to MIT (the number rated in the world for physics) and noticed a lot of similarities. In fact, I only noticed two major differences: OIST does not focus on tests as much and it is more selective. Overall, I enjoyed the entirety of the mid-program meeting.
Learning Japanese this summer has proven to be quite difficult, mainly as a result of the speed in which we had to learn it. I am taking an additional course at Chiba University, which happens to be the same as our three week course just expanded to a 12 week summer course that started in April. Despite it being the same class, the vocabulary that is used is slightly different from the terms that I had previously learned; however, these are often subtle. I would have to say that my confidence level in speaking Japanese has improved, but I feel my ability to understand what is said has improved very significantly; also, my understanding of the structure, particles, and appropriate pause points has increased. In addition, I feel that I have begun to learn some of the nonverbal communication. My experience in Japan has neither increased nor decreased my interest in the Japanese language, but I have realized that the language consists of a lot of intricacies that extend beyond the scope of the language, such as the use of formality. To be honest, each day in Japan I struggle to communicate, but I feel I have succeeded in doing so thus far (for the most part anyhow). In general, I resort to utilizing various ways of saying the same thing and I attempt to illustrate what I am trying to say on the white board. As a result of this challenge to communicate, I have learned a lot about how we communicate in general, and I have certainly learned a lot about the English language as I have tried to explain some of the more intricate concepts, such as: connotation, denotation, sarcasm, tone usage, etc.
Research Update: Unfortunately, there has been miniscule progress in obtaining the MFM images. We have taken scans of sample one and two after being placed in a ~46mT field created from to permanent magnets and then removed before scanning. These scans were with rotations of 300, 315, and 330 degrees clock-wise with the zero degree mark defined with the Y-branch samples orientated downward. The resulting MFM images were not nearly as polarized as in the previous set-up in which the samples remained in the field. Recently, we just finished the new stage design that will allow us to scan the samples in a permanent field created by one magnet. This apparatus will allow us to observe an incremental range from ~1mT to ~36mT, which is ideal to observe some of the behavior simulated in Professor Bird’s lab. One focus is the regions where the magnetic resistance drastically decreases.
Usually my mentor and I have difficulty explaining our ideas to each other, but the largest misunderstand so far would have to be from simply trying to explain what is currently going on. While we were developing a new apparatus that would produce a magnetic field with a lower magnitude, I had to remove the glue that was used to hold the core while we cut it with the diamond saw. This glue melts at a hundred degrees Celsius, and as a result we utilize the hot-plates that are in the clean room. When I went into the clean room to use the hot-plates, they were already in use by another group. I was kindly asked to wait until they finished and then I would be allowed to use it. Rather than bringing the core outside the clean room, where it could be broken more easily, I decided to leave it on one of the tables in the clean room. Seeing me exit the clean room, my mentor asked if I had finished removing the glue; I responded by saying that the core was in the clean room while I was waiting for the hot-plate. He thought I meant that I had left the sample on the hot plate and I was waiting for the hot-plate to finish heating up. As a result, he ran straight towards the clean to fix the problem, while I chased after him trying to clarify. I managed to explain what was happening by the time he had finished putting on his clean suit. He seemed rather relieved once I clarified.
Research Update: Unfortunately, we have just recently finished the stage design and the surface of our samples is covered with dust (despite always remaining in the clean room). These dust particles, not only ruin our topographical (AFM) imaging, but our MFM imaging as well. We are currently working on a way to resolve the dust issue and hope to begin scanning it with the new stage. We are still unsure as to what parameters (various distances and angles) we want to observe.
I interviewed Aoki-sensei. He got a PhD in Material Science, because he was interested in doing experiments to reveal unknown matters. Aoki-sensei felt that being a student in Japan is characterized by long nights, lack of sleep, and seldom (if any) questions are asked either during or after a lecture. He has only been an Associate Professor, and after obtaining his PhD he became a research associate at Chiba University. The lab Aoki-sensei oversees contains a cleanroom for semiconductor fabrication and a low-temperature room; the lab is focused on conducting experiments. Japan does not have military funding for research, which is different from the US. Japanese labs are separated and as a result require their own equipment rather than sharing common equipment. Aoki-sensei thinks this stems from the historical apprenticeship within Japan. In 2004, Aoki-sensei was a visiting researcher at Arizona State University for one and half years. Having international researchers in the lab provides additional motivation for research, and recently it appears that the Japanese students are becoming less hesitant towards speaking English, according to Aoki-sensei. The advice he would give for students preparing for a career in research is to try to always work with your own ideas/thoughts.
Research Update: This week, we have had many complications in our experiment. One of the major problems is the amount of debris on the surface of the samples. As a result we are unable to continue experimenting with the same samples we used previously; we are, however, trying to use other samples located on the same substrate. When we observed the effects of a constant magnetic field produced by one magnet, with different set magnitudes for each scan, we noticed that the polarity of image did not change despite changing the polarity of the magnetic field. Therefore, we changed the tip and rescanned the image, and we observed a change in polarity. Since then, we have been attempting to reacquire the initial scans, but this is not going to well. Some of the problems are: the flattening of the scanning tip, structural damage to the T-bar sample, and debris on the sample. We have utilized several methods to clean the surface, but it has only slightly helped the scans. Currently, we are continuing to clean and rescan the sample, and I think that will carry on throughout the rest of the week.
No Report Submitted
Research Internship Overview: Throughout our experiments we attempt to illustrate the various magnetic domains in the Cobalt Y-branch structure resulting from different external magnetic fields. Also, the orientation of the sample in the field is changed throughout the experiments. We are conducting our research to obtain images that correspond to simulations we received. We utilized Magnetic Force Microscopy (MFM) to measure the relative attraction/repulsion between the tip and sample, which allows us to represent the domain structure based on the magnetization of the tip. Observing the domain structure within the Y-branch samples provides further insight into induced magnetic behavior; furthermore, the goal of our research is to observe the regions where there is a shift in the magneto-resistance. Understanding this shift may allow these structures to be used for computing or other device applications. In addition, these results can be utilized to enhance or compare to the existing simulations. Our results consist of: non-uniform domain structures for temporary single magnet exposure, polarized domain structures for permanent dual magnet exposure, and non-uniform domain structures for temporary dual magnet exposure.
The NanoJapan Program is intense, but if you can manage to muddle through it, there is so much to gain from this experience. I would highly recommend always asking your labmates about what they like; not only do you show interest, but you also can try new things.