My research emphasis is optical interconnections with highly integrated of photonic circuits. Like electrical circuits with billions of transistors on a single chip, photonic integration circuit (PICs) are capable of jointing a large number of functional optical components (e.g. waveguide, semiconductor lasers, modulators, photodetectors) on single chip in order to realize complex functionalities and superior performance. This is a promising solution for future high-speed, ultra-compact, cost and power effective optical interconnections by scaling down the device footprint and scaling up the integration density.
We are most interested in silicon – one of the richest elements on earth, which is one the best options for optical integration by means of the availability of large wafers (up to 450 mm in diameter nowadays) with lower unit prices. Additionally, high-density photonic integration on silicon benefits from the advanced CMOS fabrication techniques that are developed by the IC industry. We, here at UCSB, have built a platform on silicon photonic integrations – including silicon components as well as other materials heterogeneously integrated on silicon e.g. indium phosphide based quantum wells (QWs) and gallium arsenide based quantum dots (QDs) for efficient laser sources on silicon.
I would like to mention the American Institute for Manufacturing Integrated Photonics (AIM Photonics) project at UCSB. As the West Coast Hub of AIM Photonics, the UCSB photonic groups are aiming to accelerate photonic integration to overcome the data communication bottleneck in next decade and convert this achievement to into manufacturing productivity.
The field became more and more attractive to me when I studied it further. This is an integrated discipline that requires different background knowledges and skills. I am big fan of engineering. Designing and fabricating devices from sketches gives me a strong sense of accomplishment. I feel confident and excited in this field because I believe it is fast-growing and plays a critical role in modern IT technology that will also play a more important part of our future daily lives.
We are living in the “information blasting” age, enabled by the fast-growing information technologies, including modern optical communication technology. Not only is the world connected by light through the submarine optical fiber cables, today’s internet network is enabled by high speed optical links in data centers. In the near future, optical interconnections will replace copper wire and pins in short links, e.g. between the processor and memory or among the processor cores in the computer, in order to solve the current I/O bandwidth bottleneck. Such chip-level optical communications require large bandwidth density, low power consumption, so there is a strong motivation to develop high integration density, high performance and low volume photonic integration circuit. As a milestone for this application, we have just achieved a state-of-the-art, highly integrated transceiver network on a single silicon chip with hundreds of effect units with a maximum transmission speed up to Terabit per second – which corresponds to a data rate that can transmit 50 channels of 4K media in one second!
I don’t think I can find a better place than UCSB to work in the research field that I am working in. UCSB has been a leader in the photonic integration area for the past 30 years and is now the West Coast Hub of AIM photonics. Plus my advisor Prof. John Bowers is a pioneer in the field of silicon photonics. The close relationship between the ECE department with industry as well as the beautiful beach outside the ECE Department’s building strengthened my determination to come here.
Indeed, teamwork is always the key in solving difficult issues in research work. The ‘team’ includes my advisor, experts in the group and department, and collaborators outside of UCSB. We have routine meetings and constant one-to-one discussions throughout the project timeline. We report progress, discuss issues and concerns, exchange opinions and make decisions. The meetings and discussions are critical in research work for proper planning – firstly, being prepared and concise can make communication efficient and secondly, it’s equally important to have independent opinions in the collaborations. Knowing each collaborator’s role on the team and understanding one’s strengths and weaknesses helps make correct decisions when working in a group. This is where I would like to thank my advisor, Prof. John Bowers, who is always open-minded and allows us space to think freely in our research projects.
From my own experience, my suggestions to all of UCSB’s potential grad students:
1) Keeping motivated is most important. Passion is the only key to help you pass through the difficult journey of research work, plus I think it is also the top personality trait that advisors would like to see.
2) Always bring your thoughts and ideas when talking with your advisor and teammates.
3) Take advantage of the resources around you. We are spoiled here at UCSB and one should not waste the opportunity to access the field experts, funding resources and various facilities.
I just finished up my Ph.D. research work this past summer and joined the photonic research group at Hewlett Packard labs, which is one of the leading teams in silicon photonics area. I feel very excited to move to the next stage of my career. The team I am working with is dedicated to developing a photonic solution for future high performance computers. I believe we will experience a revolutionary period in next the decade or two in this field – photonic integration as an enabling technique will change the way we think about computers, or “machines” in general, and the way “machines” change our lives. I am honored to be part of this evolution and I can’t wait to see what will happen next.
I have to say that there’s quite a bit of pressure being a graduate student researcher. The pressure comes from balancing the project side, my advisor’s anticipations, and also the work with the colleagues in my group and department. It is also a wonderful training process for my career and for working with personalities and because of it I can clearly see my growth and improvement. I live with my family in town. We had our first child in 2014 and since then we have become even busier but everything is delightful. I don’t think I have done a good job balancing my school and family time and I always feel guilty that I didn’t spend enough time with them. But family recharges me for the hard research life at school and they are also my biggest motivation for working hard.
I have moved a few times around right outside of campus in Goleta, from UCSB graduate student housing and to a public apartment in town and then back to family housing after our kid was born. Our favorite place to live was at UCSB family housing, where the rent was more reasonable, and more importantly, we got to know many friendly neighbors. Santa Barbara is probably the best place I can think of to stay for a long time, especially if you live with kids. I am so glad we could stay here after I graduated and continue to enjoy the sweet climate and the charming environment.
Our lab focuses on advanced signal processing techniques for sensing and imaging systems. The emphasis is on two and three dimensional image reconstruction algorithms from scattered coherent wavefield data. Applications include high resolution radar imaging, microwave non-destructive evaluation, and medical tomography. Current topics of interest are the integration of target motion detection and tracking with image formation algorithms for increases in efficiency and accuracy.
For my senior design class, I was fortunate to be able to work on a research project in my area focused on ground penetrating radar systems under the supervision of an experienced faculty member in the area. It was very exciting to see how the theoretical concepts taught in the classroom applied to real world systems, and could be utilized to solve complex engineering problems. I wanted to be able to build upon what I learned from that experience and contribute to the field in a more substantive and meaningful way.
The ECE department has a very strong faculty that is well-regarded in the signal processing community; therefore I believed being able to work under them would be beneficial to my success. The breadth and depth of research coverage at UCSB, would also provide me with a well-rounded technical knowledge upon graduation. I was a member of UCSB ECE as an undergrad, so I was lucky in the sense that I was able to draw my conclusions from first-hand experience. I also was able to work with my advisor at that time (Prof. Hua Lee), who was a great and supportive mentor.
Working on academic research is challenging and can be intimidating as you are trying to find solutions to many unsolved questions. However, with the help of your advisor and group, along with hard work and focus you will find success. Being able to make an impact in your field and solve problems that don’t have solutions written in a book somewhere, ultimately, is a very satisfying feeling that makes all the hard work worthwhile in the end.
The professors and students at UCSB all do a good job at fostering a collaborative environment. Many professors are happy to answer off-the-cuff questions in class or office hours about student’s research and provide their expert advice. The students are also very open to discussing one another’s research topics with the hopes of potentially sparking new ideas and approaches. My research group has been involved in many collaborative projects with other campus labs and industry groups. I myself work with an outside company working on similar research in the hopes of advancing the state-of-the art of our field.
Being able to work in a group under an advisor is a key aspect of any graduate school. As an undergrad, the vast majority of what you do is individually based. Research problems, however, are often very complex and require collaborative efforts to solve. Working in a research group with successful peers and an experienced mentor is a great experience to learn how to do this effectively. The academic research model has been around for a while, and it has repeatedly been proven to be very successful. I know that my group and advisor have been very supportive and encouraging, which really makes the whole research process enjoyable.
As of now, I am mainly focused on my research work, but afterwards I hope to go into industry to apply some of my ideas to real-world applications.
The professors here are very committed to teaching and there are many excellent teaching facilities such as our electronic device fabrication labs that are not available at many other universities.
My favorite class was ECE 278C (Imaging Systems) by Professor Hua Lee. The course begins with the basic principles of imaging from optics and builds up to more complicated material at the end. It is exciting to see complicated ideas being synthesized from first principles in an enthusiastic manner.
Going into it any exam is always tough because you never fully know what to expect. There is plenty of support structure in place for you to succeed as long as one is prepared and confident it tends to work out in the end.
Teaching a class is an invaluable experience, where you learn almost as much as you would from taking the class. The ability to explain complicated concepts in a succinct manner not only helps your own understanding, but is a skill that can be applied in whatever endeavor one pursues after graduate school. I have been fortunate to TA both lab and theory based classes. The theory classes were enjoyable as you get to practice a more traditional form of teaching at a high level and see what life is like on the other side of the classroom. I also was lucky enough to TA the Senior Design Capstone (188A/B/C) classes, which has probably been my favorite academic experience at UCSB. In the class, the seniors get to put together all their skills and knowledge they have learned to design and build an advanced engineering project from scratch. It is really exciting to help highly motivated students build these very cool projects, and although the problems can be very challenging, seeing the finished products at the end of the school year is a proud and rewarding experience.
The quality of life at UCSB is very nice for graduate students. You have the opportunity to work at an excellent academic institution and live in a terrific area. Balance is always key, so I always just try to work hard on achieving my goals while maintaining a clear perspective.
People in Santa Barbara are very friendly and it is a fun place to relax with friends. I have lived in apartments, dorms, and houses throughout my time at UCSB, and as of now I live in an off-campus apartment in Goleta for a quiet atmosphere. Because the area is such a nice place to live, finding housing that fits your ideal preferences can be competitive. If you are prepared and persistent with your housing search, you will find something that works for you.
I plan to work at a local company (AKELA inc.) and also work on my research.
Focus mainly on doing good work, and try to learn as much as possible. Also, keep a healthy perspective on life while maintaining a good balance. The time will probably go by faster than anticipated, so just make the most of each experience at UCSB.
Biological systems are inherently very complex in nature, typically consisting of multiple highly non-linear molecular interactions. As a result, even relatively small networks, such as the lactose regulation network in bacteria, tend to display very complex behaviors.
One such network is the DNA damage response network which plays a major role in tumor suppression. The central hub of this network is the p53 protein; it plays a critical role in guarding against cancer development. In humans, p53 is part of a sophisticated network of proteins that mediate cell fate decisions such as the initiation of cell-cycle arrest, DNA repair and apoptosis. Aside from p53, this network includes a set of core regulation proteins among a host of other upstream, downstream and intermediate species involved in sensing, transduction and regulation.
In collaboration with the Proulx lab in the Evolution, Ecology and Molecular Biology (EEMB) department, we explored the evolutionary history of the DNA damage response network. While the p53 protein’s function seems to have been preserved for over one billion years, this is not the case for the other core regulation proteins in the network.
We use the evolutionary analysis as the starting point to partition our dynamical model of the p53 network into smaller sub-units or "modules", such that properties of the network can be inferred from properties of these modules. Using this modular analysis, we attempt to infer the function of each module within the network. Our results show an evolutionary path towards networks with an increasingly complex structure of multi-stability, which we conjecture is associated with cell fate decisions.
I will never forget that when I first came to UCSB as a PhD student in Controls, I thought I would choose any project other than one that involved Systems Biology! I met Prof. Mustafa Khammash (then at UCSB) casually and he gave me a set of papers to read. One paper that he co-authored changed my entire perspective on the field. It was a paper about calcium homeostasis in cows. The paper went on to mention that two hormones are known to control this homeostasis, although one is thought by Biologists to be redundant. By modeling the network as an integral feedback loop the authors showed that both hormones are actually necessary, otherwise after lactation, the calcium levels would not return to their nominal level. The thought that simple ideas from undergraduate control theory could be so powerful in explaining complex biological phenomena was what lead me to pursue Systems Biology related research.
Due to the highly interdisciplinary nature of my work, I find it most rewarding when I am able to present my work to both engineers and biologists in a way that they can understand.
UCSB has one of the strongest Control theory groups in the country. To get an opportunity to work and interact with the faculty here is an honor.
My advisor Prof. Joao Hespanha has been incredibly supportive throughout my PhD. He has been instrumental in me pursuing Systems Biology research, even though I had very limited prior knowledge in Biology. Whenever I have problems with my research, he is always able to offer a very simple (although incredibly insightful) solution. I'm also thankful to have a great set of lab-mates that I see every day. We have a very diverse lab with students, post-docs and visitors of multiple nationalities. When we're not discussing work, a lot of our conversations center around football (soccer) and world politics!
I hope to use my quantitative background and interdisciplinary experience in both Engineering and Biology to study and infer the plethora of data that is available about complex biological networks. I believe that this is certainly the future when it comes to studying complex biological networks. I hope to become a Data Scientist in the industry in the short-term future. I also hope to get an opportunity to teach in an academic environment, as teaching is a strong passion of mine.
The greatest strength of the program is how approachable the faculty are. I have taken so many classes and learned so much from them, in no small part thanks to the faculty. I have never felt inadequate, even when asking the most fundamental questions to my Professors in class. Of course, it is worth mentioning that the department is engaged in cutting-edge research.
My favorite courses as a graduate student are ME 215A and B (Dynamical Systems Theory) taught by Profs Igor Mezic and Jeff Moehlis. As a Control Theory student with an ECE background, I somewhat understood the underlying dynamics in systems. However, most of the focus in Control is on the design and analysis of the controllers. Taking Dynamical Systems Theory opened up my mind to how and why systems behave in the way they do, and I highly recommend all Control students with an ECE background to take these two classes.
Screening exam: The screening exam was quite an experience; essentially, 5 Professors ask you any question under the sun about all your relevant undergraduate work. Although I was extremely nervous before the exam, one of my lab mates told me something on the morning of my exam that certainly helped me, and I hope will help others as well. Don't worry, the Professors are there to help you and not to fail you. Just relax and work through the questions with them.
Qualifying exam: The qualifying exam was a less intense experience, since one is talking about one's own work. Preparing for the qualifying exam certainly helped me to organize my thoughts and my findings, which I feel is an extremely important part of the PhD. It also helped to build my presentation skills; speaking out loud in a clear fashion is certainly very different from mulling over thoughts in my head!
I am currently working on my thesis.
TA – In my first year, I taught ECE 130A, 130B and 139. Every week, I would plan a 1.5 hour lecture to deliver during the discussion section (for all 3 classes), and of course hold office hours as well. Teaching is my greatest passion, and I really enjoy being able to simplify concepts to teach students. I think it is key to bring oneself down to the level of the students. As someone who struggled with these 3 (very mathematical) classes as an undergrad myself, I was able to identify the concepts that confused me and therefore what would probably confuse other students. Graphical convolution is certainly one of the most confounding things when one first learns about it, only to realize that one will never have to use it again!
GSR – Research on its own is very interesting, which is why I pursued a graduate degree. I think the key thing I didn't realize as an undergraduate student was how challenging it can be to define a research problem, and communicate the idea behind this problem effectively. It is almost like designing your own product. What is it? Why is it useful? Why is it novel? Moreover,as time passed during my PhD and I became more familiar with the research area, the problem definition itself (along with the solution) morphed a little bit. It was unexpected at first, but I slowly got the hang of it.
I have a time table which I try to follow. I make sure I reserve time on the weekends to take care of myself (cooking, grocery shopping, cleaning), be involved in music and speak to my wife (who is a PhD student in the East Coast). I think it is also very important to stay mentally relaxed, so I do actively have to disconnect my mind from research on most nights. I also ensure that I run in the evenings a few times a week.
Till the Fall of 2014, on nights and weekends, I was actively involved in 2 student groups on campus. With some close friends, I founded UCSB Agni, an Indian Classical music and dance group that fosters student artists and organizes performances on campus for students and the community. I was also part of UCSB Ravaani, the university's South Asian Acapella team. Going for Acapella practices, making music with my friends and preparing for performances used to take up most of my evenings and weekends. I also made some great friends in the process, many of whom have graduated but are still in touch. Since then I have gotten busier with my research, but still perform sporadically around campus. I hope to be more active in music once I graduate!
Fingers crossed, I am looking to graduate by the end of this summer. So I'll definitely be here!
My advice is as follows:
1) Be patient. If positive results came quickly, we would all be done with our PhDs in a year! We are all swimming in unknown territory, but if we keep at it, results will certainly come.
2) Stay calm. Unlike in undergrad when stress levels elevate before exams and then drop, the stress slowly and gradually builds up in the PhD. I did not even realize the stress levels building up until others pointed it out to me! It helps to actively engage in research when you are at work, and actively disengage when you are relaxing. Set aside time to relax, and try to focus better when you are doing work. It also helps to exercise regularly, even if it is for a short while.
3) Avoid competition. It is very easy to get caught up in comparing the number of publications, citations and time to graduation against others. However, I think that time is better spent focusing on one's own research problem. Remember, everyone's PhD is different. The PhD is a journey in academic maturity, and avoiding unnecessary competition and barometers for success helps make it much more pleasurable.
Typical light-matter interactions have size scales in which the wavelength of light and the size of the object it is interacting with are very different. When light interacts with objects that have sizes similar to the wavelength of light, then interesting things start happening and we can actually start to control the way light behaves. In this size regime, objects exhibit a series of resonances at certain wavelengths, known as multipolar resonances. By manipulating these resonances, researchers have created new materials with very interesting optical properties beyond those of naturally occurring materials, known as metamaterials. Typically, researchers manipulate these multipolar resonances by changing the physical properties of the objects (e.g., size, shape, material, etc.). Instead, my research focuses on manipulating the properties of the light. This enables a completely different way of manipulating multipolar phenomena.
When I started college I wanted to be an engineer, but didn't know what kind. I initially wanted to be any kind of engineer except an Electrical Engineer, because that's what my father is and I wanted to do something different. But after I started taking college classes, I realized EE is actually what I really like. I enjoyed physics in high school but never wanted to be a physicist, and EE is a happy medium between physics and engineering.
I selected the ECE department at UCSB because it has a fantastic reputation and because I had lived in Michigan my whole life before then, and I wanted to experience living somewhere different. I had applied to the Master's program at first as I wasn't sure I wanted to do a PhD, but that quickly changed after I arrived at UCSB.
When things go right in research, it's one of the most satisfying feelings in the world!
Although our research group is the only one at UCSB that works on metamaterials, we collaborate with other groups for a variety of purposes. One of my labmates is working on building a specialized measurement setup, and he gets his samples from a group in the Materials department. Another labmate of mine is working on a reconfigurable metamaterial that requires a lot of semiconductor device design, and he collaborates with the Mishra and Palmstrom groups to figure out his design and to get material to actually fabricate his design. We also have collaborations with Brown University and UCSD.
I really enjoy working with my research group. We fit really well together. They are all really interesting people and I enjoy learning from them and being exposed to things I normally wouldn't be exposed to. Many of my labmates possess important research skills that I lack, and it's extremely beneficial to be surrounded by them so I can learn from them. Additionally, when I started out with Jon, my advisor, I didn't have a background in this field. Jumping into something completely new was intimidating, at first, but partly because our research group is so new (Jon joined UCSB in 2012), we were all new to the field and all learning together.
I plan to transition into a career in which I can more directly see the impacts of the work I do by bridging the gap between science and society. I don't think there are enough scientists in positions where they are regularly interacting with and impacting the public in meaningful ways, which has contributed to a disconnect between the scientific realm and the public. Specifically, I plan to go into a career related to science education or policy.
There are many knowledgeable students and professors who excel at a wide variety of research. If there is any question you have about some type of software, or some type of circuit or device you are trying to design, a useful conversation about it is just an email away. Also, many students in ECE research groups are actually from other departments which naturally encourages multidisciplinary projects.
My favorite course at UCSB was Digital Circuit Design taught by Luke Theogarajan. I doubt I would have said that at the time I was taking the course, and even though I learned only half of what was taught, even that half was an incredible amount of information. A lot of my appreciation for that class was because Luke was teaching it. He is one of those rare professors who actually takes a personal interest in the success of the students he encounters.
Preparing for the screening exam was pretty stressful at the time. I was preparing for the screening exam over the summer, when I was also doing a full time internship. I was grateful when it was over. The qualifying exam was far less stressful, since it is a presentation about my research, which I already knew. There is less room for the unexpected in a qualifying exam.
It's a see-saw. Sometimes research is extremely busy and I have a ton of deadlines and there is no balance, and other times I can breathe a little and there is time to have fun. I try to take advantage of that time when it comes.
I lived in San Clemente my first year, which was fun as I got to meet many grad students in a variety of departments. However, I have since moved into an off-campus apartment which I also very much enjoy. I am in an apartment complex where plenty of UCSB grad students live. Santa Barbara public transportation is great and it's easy to get around by bus. I also really appreciate the location of Santa Barbara in terms of where it is in the state of California. SB is about equidistant from both Yosemite National Park and Las Vegas. There are so many places to explore in this region of the U.S. and they are all a road trip away, which also makes SB a great place to live.
This summer I stayed in SB and did research.
The typical advice is to make sure you and your advisor get along and have a good relationship, but I would say it is equally if not more important to make sure this is true for your labmates as well. They are the people you will see and interact with the most often. Being friends with them and genuinely liking them will make grad school life much more bearable. Also, after you stop taking classes, realize that there is no longer an externally imposed structure on your life. Recognize this and impose your own structure so you make sure you get things done.