The are solid foundations for my future research

The most important scientific and technical achievements in the mid-twentieth century, in
my opinion, is the invention of semiconductor transistors and the development of computers
based on those transistors. This achievement led to the information revolution, which not only
changed the way people entertain, but also changed ways of working, especially for studies and
research. In the near future, the development of quantum computation and nanophotonics will
lead to another information revolution, and I am determined to lead this scientific progress. To
realize this goal, I have achieved excellent performance in relevant courses and participated
in four research projects about optics and nanophotonics in my undergraduate study. With
proficient theoretical and experimental skills acquired during these years, I have developed a
comprehensive understanding of this field.
From my point of view, theoretical knowledge and computational skills are two key elements
for an excellent researcher, since they provide strong guidance and useful techniques for conducting
research. Based on such a belief, after I entered University of Science and Technology
of China (C9 League; Ranking: 3; Ranking System: US News Best Global University in China)
for my B.S. degree, I tried my best to gain knowledge and skills in classes and achieved A+ in
many of my core courses, such as Electrodynamics, Quantum Mechanics, Solid State Physics
and Computational Physics. These basic physical concepts and analytical methods are solid
foundations for my future research experiences.
After classes, I also developed a great passion for conducting experiments and I tried to improve
my experimental skills as much as possible. My first research project was “Preparation of
Bessel beam”. As the leader of a group of four students, I wrote a C program and then designed
and set up an optical system to test the properties of the spatial light modulator. Then I wrote
another C program and displayed the hologram on the spatial light modulator. By using this
hologram, we managed to prepare the Bessel beam. Our project won the first prize in the
Level 4 Physics Experiment. This experiment not only taught me how to adjust the beam path,
but also taught me how to design an experiment scheme properly with limited experimental
devices. As a collaborator of this team, I quickly valued strong communication skills as an
effective tool for team meetings. As a leader of this team, I managed to get everyone on the
same page and set the ultimate goal which motivated us through the hardships.
To further strengthen my research ability, I joined Professor Changling Zou’s group in Key
Laboratory of Quantum Information, University of Science and Technology of China. After
a discussion with Professor Zou, I decided to do some theoretical research about the Faraday
effect in the yttrium iron garnet microsphere. I derived the theoretical formula based on
some relevant papers and used COMSOL-Multiphysics to test my formula. Then I successfully
wrote a Mathematica code by using the formula to calculate the frequency shift between
counter-clockwise light and clockwise light for each whispering gallery mode. This experience
enhanced my awareness of the steps to efficiently carry out a project. First, I need to develop
a clear understanding of the project’s major problem and what I expected as the result. Then
I need to choose an appropriate method and painstakingly run experiments to achieve it. Although
there were many obstacles that frustrated me and made me ponder whether it was
worth all the effort, my great faith in science built up my confidence and guided me to conquer
all the difficulties. I finally overcame them and enjoyed the excitement of solving problems. For example, when I tested my formula for the first time, I found that the frequency shift I derived
from my formula was inconsistent with what I derived from the numerical simulation. For a
long time, I thought that my formula was incorrect or the settings of the simulation were inappropriate.
But after several rigorous inspections, I failed to find any problems. Then I soon
realized that the frequency shift might have a second-order term, but I was only interested
in the first-order term. After I eliminated the second-order term, the two results fit together
very well. By solving this problem, I realized my potential to be a researcher who truly enjoys
solving complex problems.
In the summer of 2017, I did a summer internship in Professor Hong Tang’s group in Yale
University. My project was to design a superconducting electro-optical modulator, which is
a key device in the superconducting quantum computer of the future and is exactly what I
want to do in the future. After thoroughly investigating its background, I designed the basic
parameters of the optical waveguide by using COMSOL-Multiphysics. Then I discussed the
structure of this modulator with my mentor and Professor Tang and calculated the optical
loss by using Fimmwave and Fimmprop. At last, I got V ? with a limit of 3dB optical loss
successfully by writing a MATLAB code simulating our designed structure. This summer
internship not only introduced me to the major problems top scientists are concerned about and
the reasons behind their importance, but also cultivated my skills in designing nanophotonic
devices. It broadened my horizons and convinced me that nanophotonics will be my lifelong
career direction.
To sum up, I have gained fruitful theoretical knowledge and experimental skills in nanophotonics
and I seek to passionately devote myself to this field. I hope to pursue a Ph.D. degree in
this field to further enhance my abilities. While in summer, I studied electro-optic effects in
electro-optic modulators in Professor Hong Tang’s group. Now, I am doing some research on optomagnonic
effects in the yttrium iron garnet sphere. With these research experiences, I have
had a good understanding of interaction between different harmonic systems in nanophotonic
devices and I was highly attracted by their potential applications in classical and quantum
information processing. Therefore, I eagerly hope to join Professor Hong Tang’s group and I
want to design and fabricate other novel nanophotonic devices and further study nonlinear
optical effects in these devices during my Ph.D. study. I am sincerely looking forward to your
favorable review of my application and hope to continue my journey of discovery and invention
in Yale University.