The University of Tokyo
Status: B3 Expected Graduation: March 2018
Research Host Lab: Kono Lab, Electrical & Computer Engineering, Rice University
Research Project Poster: “Temperature dependent absorption spectrum of exfoliated InSe”
Why Nakatani RIES?
I need various research experiences to contemplate for my future career. Acquiring a firsthand research experiences in different institution broadens my scientific perspective and insight. I believe these enhanced are specifically valuable and helpful when to determine a laboratory to pursue my Ph.D. in a graduate school and when to consider the research topic. Also during the intensive research program for a limited period of time, I will realize an efficient approach to plan and conduct research. I believe we should thoroughly practice the efficient approach to become a productive researcher in the future, and more essentially, to immerse myself in more important work.
I hope to conduct an experimental research in the field of Plasmonics and my final goal is to publish my second paper (partially) based on the experiments in Rice University. Since science relies on the communication among researchers, any unpublished scientific result does not contribute to the science regardless of its importance.
Goals for the Summer
- Publish a letter (partially) based on the experiments conducted in Rice University.
- Make good friends with the colleague participants from various backgrounds and to be enlightened from them.
- Get a good mandolin!
- Enjoy the culture and atmosphere in Texas!
Excerpts from Nobuyoshi’s Weekly Reports
- Week 01: Arrival in the U.S.
- Week 02: First Week in My Research Lab at Rice
- Week 03: Interview with a U.S. Researcher
- Week 04: Reflections on English Language & Life in the U.S.
- Week 05: Research in the U.S. vs. Research in Japan
- Week 06: Final Week at Rice & Research Poster Presentation
- Week 07: Visit to Washington, DC & New York City
- Final Report: Reflections on the Nakatani RIES Fellowship
Week 01: Arrival in the U.S.
During the pre-departure orientation in Tokyo, the Japanese and US fellows had discussions and opportunities to talk with the executives and secretary of the Nakatani Foundation. From my point of view, US fellows seemed excited by their research experiences in Japanese universities. I was inspired by their positive attitudes and was strongly encouraged by officers of the Nakatani Foundation to study and play hard.
As soon as I arrived to Houston, I noticed the kind personality of Texans and surprisingly significant difference in temperature between the air-controlled inside and humid outside. I also realized the culture of contracts or stating clearly for anything in a little while. Take public areas in the US such as airport, buses, hotel, and university for example, their policy are explicitly noted on the wall. One can attribute these phenomena to American common personalities but I would say that they elaborate and maintain social systems by mentioning leading to important social differences from Japan, or Asian countries.
At Rice University, as Prof. Kono mentioned in the seminar, I felt it has a good and collaborative atmosphere to facilitate research projects. Prof. Kono seems to enjoy collaborating with confidence at Rice University. I recalled someone saying that there seems a correlation between being productive researchers and being modest persons in the U.S.
Question of the Week
What must Ph.D. students concentrate in while they are students? Productivity, acquiring skill set, connections, etc.?
- This is a very good question and one that every Ph.D. student should ask themselves before starting a graduate degree program. This is also a question you should ask yourself at many times throughout the 5 – 7 years you may be working on your Ph.D. as the answer/s to this question may change over time. What you need to concentrate on or improve in year 1 might be different from what you need to concentrate or improve upon when you are writing your dissertation in year 5, 6, or 7. First, it is important to remember that the most important relationship you will have as a Ph.D. student is with your professor/advisor. Choose your advisor carefully and be sure to ask him/her what they value most in a Ph.D. student and where they think you should be focusing your time (and remember to ask them this question a number of times throughout your Ph.D. as their answer may change over time too). When you are working on your coursework it will be very important that you do well in those since if you don’t pass your classes, particularly your qualifying course/exam, you won’t be able to complete the degree. But you have to balance your coursework with your research project and expectations for spending time in the lab too. This means you may need to manage your time very well to make sure you, for example, wake up early to study for your classes at home (or in your office) and only go into the research lab after you’ve completed your studying/assignments. You also may need to set aside time for writing papers or your thesis/dissertation in a similar way as ‘doing research’ is the fun part and most Ph.D. students struggle most with the ‘sitting down to write’ part. You may also have teaching or grading requirements for your graduate assisantship or your advisor may ask you to mentor/advise/help younger students in your lab. All this at the same time when you are trying to setup and successfully do your own research projects/experiments! It is not easy and time management and being able to prioritize what you should do first each day is a very important skill. Your professor/advisor may be able to help you with this, but you should also be curious to ask your lab mates how they organize their time. What works for them? What do they recommend you concentrate on the most at different points in your Ph.D. studies? If they could change something about what they did as a first year graduate student, what advice would they give you? There are also lots of articles on what it takes to be a successful Ph.D. student but, ultimately, the answer rests largely in what you need to do to stay motivated and flexible to adjust to changing realities over time.
How did you prepare for your research internship at Rice University before leaving Japan?
Before arrival to US and seeing my supervising professor Prof. Kono and my mentor Katsutani-san, they briefly described via email that spectroscopy of InSe under high magnetic field as the research project I would engage in, and listed papers for reference. I focused on trying to understand their experimental set up at the beginning, because I am not familiar with either semiconductor physics nor solid state physics. Understanding the experiment set-up would help me practice assimilating the project as a whole. It was beneficial to have a conversation before coming to the U.S. with a former intern student, Kota Katsumi, who worked in the Kono Lab as part of the 2016 TOMODACHI-STEM program, and who is now a master’s student at the University of Tokyo. He introduced me to a basic textbook which explains optical physics of semiconductor, and how nice our mutual mentor Katsutani-san is.
Week 02: First Week in My Research Lab at Rice
From my point of view, my mentor and graduate students in the lab seem to work hard showing their professionalism sometimes. This is understood partly because they are paid and face competition or comparison among all US universities. I think, although professionalism is not a perfect attitude towards science, I could learn a lot though their attitude.
By spending time, I find it necessary to behave as a moderate, consistent, and self-confident person while in the US. In other words, behavioral assimilation is much important than linguistic one. Although the ability to speak fluently and logically in English definitely helps with deeper understanding of the US culture, I realized the most important thing is to behave as they do for taking a part of their society because otherwise I am just a foreigner who speaks English well. I would focus in this perspective so far.
Question of the Week
What distinguishes research university and education university?
- In the U.S. there are many different type of institutions of higher education from 2-year or community colleges, to liberal arts colleges, to research intensive universities. What they all have in common in the foundational belief that a bachelor’s degree should provide students with a well-rounded education that enables them to not only take coursework in their chosen major/subject area (such as engineering) but also requires them to take liberal studies/general education coursework in subjects like history, social sciences, humanities, etc. to provide them with a broad understanding of education and learning overall. Then, as you progress through master’s towards your Ph.D. you become narrower and narrower in what you study and focus in on a specific field or research topic that is of greatest interest to you. Therefore, most PhD students would not take coursework outside of their department or required degree coursework but undergraduates can take classes in any department/field that they are interested in.
- The two broad categories of four-year institutions (those that offer bachelor’s degrees) is a liberal arts college vs. a research intensive college. Liberal arts colleges tend to be smaller and only offer bachelor’s degrees (perhaps a few master’s) and the faculty and students focus most of their time and attending on teaching and classroom based learning. In a research intensive institution, the universities tend to be larger and offer a more varied array of programs and degrees with a strong emphasis on graduate degrees at the master’s or Ph.D. level. Faculty tend to focus much more of their time managing their research grants and the graduate students in their group and may only teach 1 or 2 courses each semester; sometimes teaching only graduate level courses. However, these categories do overlap. Many liberal arts schools enter into partnerships with larger universities nearby to offer research opportunities to their students or to facilitate transfer into graduate degree programs at other schools. Liberal arts or general education courses are required for all undergraduate students at research intensive schools as well; and many students at Rice even double or triple major in not just an engineering degree but also a degree in a different field too.
Research Internship Update
My Japanese mentor, Fumiya Katsutni, and I conduct spectroscopy of InSe under high magnetic field for the intern project. Our scope is to understand the optical properties of InSe multilayers (thin film) in near-infrared range by using strong magnetic field, or polarization/field dependent spectrum which originates from each exciton states. InSe is a layered (2-dimentional) semicondoctor that can be applicable for future high-efficiency thermal-electrical devices, and quantitative study of the magneto-optical effect has not been done for thin film, to the best of my knowledge. We use a pulsed (intense/short time) magnetic generator called RAMBO (:Rice Advanced Magnet with Broadband Optics) which is one of advantageous tools in Kono lab enables us to apply strong magnetic field and to inject broad light to a sample simultaneously. Although the experimental system has been well-established in the lab, I could help my mentor with sample preparation and the optical adjustment to some extent.
In the followings, my research diary of second week is shared. On Sunday, my mentor and I had lunch together. He kindly reviewed their experiments, their research field, and the strength of Kono’s group. On Tuesday, I was obliged to take a laser safety training for conducting optical experiments using lasers. It was well prepared and meaningful for me in the sense that I knew how eyes (lens/retina) damage after exposure to strong laser light depending on the wavelength, how the initial symptom seems, and how to prepare for avoiding laser damage. On Wednesday, we had a relatively small meeting connecting RAMBO users. A post-doc researcher guided the conversation and they seemed to discuss about practical experiments. On Friday, we had monthly group meeting of Kono lab. Graduate students reported on the current progress of their projects. Friday evening, Kono’s group celebrated a new Ph.D. holder (Chinese female) who just acquired her Ph.D. three days ago at Valhalla, a bar at Rice University. Professor Kono kindly hosted his colleagues including me with champagne. In the small talk there, I was really surprised that another Ph.D. student (Chinese female) already wrote a review paper which cites 200 papers. That weekend I had some chores to do and went to the university. I met a Ph.D. student (Chinese guy) in Kono lab, and was again surprised by his insightfulness and contribution to the laboratory. We discussed some aspects for pursuing Ph.D in the US. He highlighted to me the advantages of US graduate school from the viewpoint of professional career opportunities and that most highly cited journals are in the US. When I told him my interest of X-ray generation he suggested some strong research groups in the US which seem to develop promising tools for me.
Week 03: Interview with a U.S. Researcher
I was grateful to have the opportunity to interview a graduate student in Prof. Kono group. He is the Chinese student that I talked about in my last week’s report who is a Ph.D student in the Electrical and Computer Engineering Department. We talked about his background, research project, and perspective reflecting his experiences. He graduated from a Chinese university majoring in physics and chose to pursue his Ph.D. at Rice University working in in the Kono Group owing to the consistency with his bachelor’s research and the productive environment of Prof. Kono’s lab; where they regularly publish high-quality papers. His current research project is focused on terahertz (THz) spectroscopy of condensed matter, or low energy excitation of strongly correlated system.
He mentioned two differences between Rice and his home university in China. He said that in terms of the responsibility of professors in the U.S., they take more time preparing for their classes as compared with a typical Chinese professor. This can be attributed to a more developed assessment system of studying satisfaction for students, obligating professors to spend time on classroom teaching for the tenure process. He also said that Rice provides good residential education for undergraduates in multiple dormitories and colleges, as well as excellent discipline for its graduate students. Residential education is not as common as in US in China; except for in Hong Kong. His observation sounded coherent and interesting to me. I appreciated the meaningful and comfortable conversation he had with me about these differences.
Research Project Update
On Wednesday, during free time, I went to the swimming pool at Rice University for exercise and relaxation. I am becoming a better swimmer.
On Friday, my mentor and I went to a working factory at Rice University to hand-craft optical elements. According to the regulations in the factory, everyone must wear safety glasses without exception to avoid unanticipated accidents. But I neglected the warning at first and my mentor, who already wears ordinary glasses, did not notice either. As soon as the supervisor in charge of factory safety noticed me without glasses, he kindly gave me a strong warning to comply the regulation, and introduced detailed cases actually happen at Rice and other universities when students failed to abide by safety regulations. He also said by observing us that “Most of accidents are happened when you are tired or distracted and not paying attention. If you are in haste you should try to slow down any procedure. Otherwise I need to tell misfortune to your parents.” We learned a lot from his example.
On Saturday, my mentor conducted experiments as usual and I observed him and did some chores. During down or idle time while we were waiting to use the experimental equipment, we went to Jinya which is a restaurant that serves Japanese ramen in Houston. It was much better than expected, and it confirmed for me that foreign food in America is good. It was funny hearing that a Chinese colleague in our lab does not like the ramen at Jinya because he says he can make better.
Week 04: Reflections on English Language & Life in the U.S.
In the lab, I rarely have opportunities to brush up on my English conversation skills because most my professor and mentor are Japanese, though the discussions in my native language always help deepen my understanding. To compensate for this situation, I try to speak with the other graduate students in my lab who are not from Japan and also try to read as many papers in English as possible.
Outside of the lab in my daily life, I feel it is fun to speak with Texans but sometimes it can be difficult to hear them because they speak fast; even now after I have been in the U.S. for a month.
Question of Week
How important do you regard sleeping as a student/researcher?
- The ideal amount of sleep someone needs varies a great deal by individual and can also change over time as we get older as well. You may see that some people in your lab seem to need only 6 – 7 hours of sleep each night and they seek fine. But, other people may need at least 8 – 9 hours of sleep each night to really work effectively. Learning how to pay attention to what your body needs to be the most effective student and researcher possible is an important skill if you choose to pursue graduate study. You may realize you need to go to bed earlier than others around you because not getting enough sleep each night negatively affects your academic performance or research progress. Or you may find that you do your best writing or studying by waking up early each morning to work at home or in your office when it is very quiet and there are fewer people around (or vice versa and you do your best work late at night).
- Typically, in graduate school or when working in an academic research lab in the U.S. what is valued is how effective you are when you are in the office or lab. So, if you find that you work best by coming in from 10:00 – 6:00 PM (or some alternate schedule), then you can speak with your professor or research mentor and/or professor to ask if it is okay if you shift your work schedule. However, how flexible your research/lab hours should be will vary by the culture of your research lab. If you work in an industry job/internship where you are working in an office setting the most typical working hours will be 8:00 – 4:30 PM or 9:00 – 5:30 PM. In the U.S. your advisor, professors, and/or employer will expect that it is your responsibility to ensure that you get enough sleep each night and are well-rested enough when you come to work to be effective and perform your tasks well.
- One other difference you may find between Japan and the U.S. is there may not be as many opportunities to close your eyes or take a quick rest either in the office or in class. In the U.S. students and workers are expected to be alert, active, engaged, and effective when they are in class, working, or in the research lab. You come into class or the research lab to work and accomplish specific tasks for that day. Then, once your work is done for the day you can leave the office/lab and go home. Since we often commute by driving rather than public transportation we also cannot nap or rest while we are commuting like you often can on the subways or trains in Japan. Overall, America is a very busy go-go-go society and we often don’t place a high value on napping/resting or other self-care as a normal part of our day. Truthfully, this means that many people in the U.S. are chronically sleep-deprived and, in a research lab, being sleep deprived or too tired is a safety issue because you are more likely to make a mistake when you are sleepy. This is something that people are beginning to talk more about now though and realize that lack of sufficient sleep also has negative health impacts well.
My mentor and I have acquired some disappointing data that likely indicates a poor quality sample, which might not be suitable for magneto-optical spectroscopy. He quickly consulted our supervising professor so we can purchase a new commercial sample, but we slightly shifted emphasis of our project to a different spectroscopic experiment considering the remaining time. I felt happy to have the opportunity to making up and adjust the experimental system many times by myself.
Week 05: Research in the U.S. vs. Research in Japan
From the viewpoint of the research environment, I have not noticed general differences between American and Japanese as far as I know. Even so, I have noticed slight differences of graduate students’ attitude or culture. First, American students tend to spend more time on weekends relaxing to control their mental stress while concentrating on work during the weekdays compared with Japanese. I learned about the importance to take a break to refresh (work/life balance) for one’s productivity because I think contributing energy and spending time are inevitably important for conducting a good research. Second, research training for using common facilities seems rather systematic in the US, or at Rice. This can be understood as the reflection of diversity of the US students with various background and knowledge. Last, I noticed an interesting phenomenon when describing “experiment”. Some Americans call a well-designed and adjusted experiment a “good experiment” to appreciate the contributors, leading to productive atmosphere. In contrast, an experimental system is rarely expressed by Japaneses with such subjective adjectives as far as I know, reflecting their careful and modest attitude for science. These cultural differences between the US and Japan have broadened my perspective.
Question of the Week:
What are known characteristics of Texans (people in Texas) among Americans and Texan cultures? I am strongly interested in why some Texans are so friendly.
- Yes, friendliness is one stereotype or common characteristic of Texans (though this is also said about people who live in other Southern states or the Midwest too). Houston is also very unique in that it is a large city that is known for being very welcoming to migrants from other states and immigrants from other countries. Houston is one of the most diverse regions in the entire United States. Here’s a list of some other common stereotypes about Texas but remember, stereotypes are generalizations (not rules) and there is a lot of diversity among cities, groups, and individuals in Texas and elsewhere in the U.S. too. The friendliness stereotype though, that is is definitely true about Texans. 🙂
Research Project Update
We have measured absorption spectrum of an InSe sample which was bought from a manufacturer, to confirm the quality of the sample without magnetic field. Better quality than old sample seem to be indicated based on the spectrum. I did not understand why my mentor did not pay attention to the sample development method, impurities nor the crystal phase of the sample, even though he consider the noisy signals come out through the last experiment because of the sample quality. Even so, discussion about the measured signals with my mentor and other graduate students was beneficial for my understating in semiconductor physics and preparation for the poster presentation.
Week 06: Final Week at Rice & Research Poster Presentation
To look back at my internship in the Kono Lab, I learned that it is necessary to concentrate in a specific field by pursuing a Ph.D. degree from a small conversation with Prof. Kono and observations of Ph.D. students. Seeing the graduate students and getting a good overview of their specialty by reading and growing up their strengths in experimental techniques, I was strongly stimulated too. Even though my research focus for my Ph.D. may be different from what I have done in the Kono Lab, the stay and the research experiences would be highly helpful to me in the future to help me determine the potential field to focus on.
I sometimes felt there was difficulty in communicating with my mentor, because he is busy with taking classes and his experiment. Even so, I realized the importance of positive or aggressive attitude for a scientific communication in the U.S. and the importance to be a handy student for my mentor/supervisor to build up a trustful relation.
During the poster session at the RCQM colloquium, I had a meaningful discussion with a post-doc researcher and learned more about the detailed data interpretation of the spectrum and the origin of the temperature dependency in the language of quantum physics. I also met the mentors of the other Japanese fellows and had nice conversations about US culture.
Question of the Week
How do American students learn technical writing? I sometimes feel difficulty in technical writing even in Japanese.
- Yes, technical writing is something that is not easy to learn and that native English speakers struggle with sometimes too. At Rice University, the Rice Center for Engineering Leaderships Communication program offers special classes and workshops to help students with technical writing and presentations and the Center for Written, Oral and Visual Communication also offers workshops on technical writing. These campus-based resources can help students become better writers overall. Your PhD advisor may also help but, depending on how busy they are, the level of detailed feedback they provide on your writing may vary. It is very common for students to ask other lab group members to help them proofread their technical writing and to take advice and help each other as well.
Final Research Project Update
Research Project Poster: “Temperature dependent absorption spectrum of exfoliated InSe”
Authors: Nobuyoshi Hiramatsu, Fumiya Katsutani, G. Timothy Noe, and Junichiro Kono
Thin layered materials have gained attention over the past few decades. Indium monoselenide (InSe) is a member of such layered materials that can be applicable for transparent, flexible, and energy efficient electric devices[1-3] and thermal devices.
We made a thin sample on a quartz substrate by mechanical exfoliation with scotch tape, and characterized the sample quality by measuring the absorption spectrum of the sample with changing sample temperature. An optical system was designed to measure transmission spectrum of a small (~80μm) flake as shown in Fig.1.
Fig. 2 shows the spectral absorbance as a function of sample temperature. A feature at 300 K around 2.5 eV became significant and
shifted to higher energy as the temperature of sample decreased (see a blue circle). By observing temperature dependence of the features and considering the band structure of InSe, we attribute these features to the direct transition between the second highest valence band and the lowest conduction band, indicating sufficient sample quality for optical characterization.
In conclusion, we successfully exfoliated a thin InSe sample, and made an optical setup to measure transmission spectrum of a small (~80μm) flake. We confirmed the sample quality by observing the optical excitation from the second highest valence band to the lowest conduction band. Magneto-optical studies of exfoliated InSe samples correlated with the sample thickness are now proceeding, to determine the fundamental parameters of excitons (size, binding energy, spin, dimensionality and so on).
- S. Lei et al., Nano letters 15, 259 (2015).
- S. Sucharitakul et al., Nano letters 15, 3815 (2015).
- S. Reddy et al., Nano letters 14, 2800 (2014).
- G. Han et al., Small 10, 2747 (2014).
- N. Kuroda and Y. Nishida, Physica 105B, 30 (1981).
- A. V. Stier et al., Nat. Commun. 7, 10643 (2016)
Week 07: Visit to Washington, DC & New York City
In Washington DC, we visited Howard University, the Japan Society for Promotion of Science (Nihon Gakujutsu Shinko-kai), and Office of Science & Technology Policy at the White House. Dr. Thomas Searles guided us around the campus at Howard University and gave us tours of their experimental equipment in the physics department. He also gave an interesting lecture of his research and talked about his career and when he was a Ph.D. student under Prof. Kono at Rice University. When we went to the Japan Society of Promotion of Science at Washington Office, the Director Dr. Nozaki, introduced opportunities for research fellowships (Kakenhi) to us, and we had a casual discussion with him. Mr. Kei Koizumi who is working for federal science policy at the Office of Science & Technology Policy led us in the White House and we had a casual discussion with him too. Based on his talk, I realized the diversity of contributions to science in the US as well as fundamental importance of their works to establish the policy and education for facilitating scientific research and development. I would say, the whole opportunities in Washington DC were very enlightening for me.
In New York City (NYC), we went to Columbia University and I met with three professors thanks to the efforts made by Prof. Uemura to arrange visits for us at Columbia University. In my visit to Prof. Billinge’s laboratory, I had opportunities to discuss physics of beam-line and X-ray with their graduate students as well as learn about their lives as a student. With Assoc. Prof. Bailey, I learned about magnetic dynamics on a crystal surface, or spin-Hall effect. It was interesting for me to know about the detailed experimental differences of the development method of the magnetic-crystal which may affect the sample quality and the surface roughness. Assoc. Prof. Narayan casually introduced their research in condensed matter experiments. The opportunities to meet with them were definitely great experiences for me to consider potential fields for my Ph.D. in Physics, and will be beneficial when to applying to a graduate school or a job abroad. During my free time in NYC, I went to Jazz bar called “Bluenote” which is one of the most historical and popular spot for modern jazz in the world. I luckily got a seat there without the reservation, and enjoyed the atmosphere very much.
After coming back to Tokyo, we had small discussion with Prof. Maruyama from the University of Tokyo. From his talk I learned a lot including the importance to see research cultures from comparative and objective viewpoints, and the need to design my career path by considering the future development of the field as well as the current research environment as he mentioned briefly.
Question of the Week
Are there any exceptional or special state law in Washington DC?
Fun fact, Washington, DC isn’t technically a state. In the U.S. constitution it states that the capital will be a separate jurisdiction controlled by the federal legislature; not an independent state government. This was done because the founders worried that if the capital were to be a state, the members of the government would be unduly beholden to it. To this day, D.C. does not have voting representation in Congress, and the federal government maintains jurisdiction over the city. That’s why when people say how many states there are in the U.S. they say “50 states plus the District of Columbia (DC).”. For more see some of these websites below:
- Wikipedia: Washington, DC
- Time: Here’s why Washington, DC isn’t a state
- 15 Extremely Weird Laws in DC
Final Report: Reflections on the Nakatani RIES Fellowship