30 Jul 2016 by mirza

Our new website is launched. We believe it is important to have online presence in this age and we will try to communicate through this site. All the updates about our research work can be found in this site.

Our site is fully static and it has the capability to be expanded in full fledge website for a big research group. The source code is still not open for all.

[an error occurred while processing this directive]
28 May 2015 by mirza

We do plenty of math, so I’d like to test out MathJax support.

Here is an example of MathJax inline rendering — $$1/x^{2}$$. And here is a block rendering: $r_{XY} = \frac{\mathrm{cov}(X,Y)}{\sqrt{\mathrm{var}(X)\mathrm{var}(Y)}}$

Now, if we’d like to get serious, we’d do something involving multiline aligned equations, like \begin{align} \mathcal{N}(t, \mu, \sigma) &= \mathrm{normal} \newline &= \frac{1}{\sqrt{2 \pi} \sigma} e^{-\frac{(t-\mu)^2}{2 \sigma^2}} \end{align} or even an inline formula like $$\sum_{t=0}^{\infty} \frac{x^t}{t!} = e^x$$.

Or we could try defining a command, like this. $$\newcommand{\water}{\mathrm{H}_{2}\mathrm{O}}$$

Buffer slides off the sides of our tubes like $$\water$$ off a duck’s back.

14 Aug 2014 by avik

## What do we work on?

Research in our group has the advantage of being both curiosity driven and needs driven. Industry is always looking for ways to design or utilize novel materials and devices for new applications. To that end, our research focuses on three aspects of nanoelectronic modeling and simulation:

1. Fundamental physics of current flow through nanosystems: Traditional CAD tools for electronic conduction are based on macroscopic concepts such as mobility and diffusion that do not apply at these length scales. Our methods include effects due to quantum interference right from the outset, along with inelastic scattering, ‘friction’ and heating due to vibrations and spins, strong non-equilibrium many-body effects, and time-dependent effects due to hysteretic switching, memory and noise.

2. Computational modeling: Here we develop the formal evolution equations into quantitative simulation tools. This includes semi-empirical as well as ‘first principles’ methods for capturing chemistry, bandstructure and transport, describing the nano-channels and contact surfaces atomistically. Special attention is aimed at multiscaling and embedding techniques to describe hetero-interfaces and surface states, as in hybrid molecule-silicon devices.

3. Device engineering: Here we combine the formal equations with numerical simulations to identify performance advantages and limitations of nanoscale devices, such as resonant tunneling diodes, switches, conductors, interconnects, transistors and electronic sensors made out of various materials such as molecules, nanotubes, nanowires, spintronic or magnetic elements and silicon quantum dots. Part of our current interests involve exploring hybrid devices operating on novel principles, such as gate-tunable scattering centers for characterization and detection, conformationally gated molecules for nano-relays, molecular redox centers and motors integrated on a silicon CMOS platform for memory and heat sinking.

## Do you have the right background?

Our research combines fundamental science with interesting applications. On the one hand, this involves a wide body of knowledge from physics to chemistry to materials science. On the other hand, much of this can be picked up in a short time (at least getting you to the point where you can start doing useful simulations – mastering the area itself is a life-long enterprise, just as in any other discipline).

Much of the background for these simulations can be acquired through a course I offer, ECE587/687, “Fundamentals of Nanoelectronics”, in Spring sessions. The course itself does not require much background, except familiarity with calculus, Matlab or an equivalent mathematical package, and some familiarity with electrostatics (ECE309), such as Poisson’s equations or Coulomb’s Law.

But the good news is that you really do not need too much of a background to ‘qualify’ for this. What you do need, however, are

A. a degree of comfort with computation and mathematics, which will be our languages of choice. B. Genuine interest and enthusiasm for the field (the Ph.D. process can be both rewarding and frustrating, and only a strong sense of commitment and an abiding love for the research area can help make this an enjoyable experience). C. A degree of modesty and an open-mind. Research in our group is interdisciplinary, and done in close collaboration with researchers from various fields (physics, chemistry, materials science, engineering, circuit theory, industrial labs, national labs, experimental teams, high-power computing, etc). It is important therefore that you do not pigeon-hole yourself into thinking that one area is somehow superior than another, because you never know which tricks picked up from which disciplines will help you in your research.

With the proper research tools and environment (which we will provide), and the proper outlook and skills (which you bring), there is a lot we can do together.

## Looking for PhD Positions?

If the work in our group interests you, you should send an email to me (keep it short and relevant), describing your interest. You can attach a short vita if you like, but please focus on relevant information only (ie, courses taken, research experience if any, grades or GPA, etc – please do not pad your resume with information about athletic meets or debate societies).

A nod from me about a match of interests does not automatically guarantee acceptance. You have to go through an independent committee that will evaluate your resume in relation to other applicants. Explicitly mentioning our group would redirect the application to our attention, which would help if the committee shortlists your application.

A typical Ph.D. should take about 4-5 years. In this time, you will work with me and possibly a few other collaborators within our group, as well as from other groups within UVA and elsewhere. Although it is hard to guarantee funding for the whole duration, we try our best to provide students with research assistantships for the duration of the graduate work. The department also has teaching assistantships that may be available when RA positions are not. So far, all our students have been supported entirely on RAs.

Working in our group will involve a mix of physics, electrical engineering and materials science. We do collaborate with experimentalists closely; however, our work is mainly theoretical and computational. There is a lot of fun to be derived out of developing mathematical and computational descriptions of materials and processes at the nanoscale that could form the basis of future devices. It also gives you the opportunity to create a broad overview of many interdisciplinary issues in science and technology, as well as develop a wide variety of numerical and computational skills that will be useful for both academia and industry. Given that theory, modeling and simulation is what you will be relying heavily on for the next few years, it is important that you are comfortable with this line of work and actually enjoy it. Go through our website and if this sounds compelling, write to us and we can talk.

## Looking for internships?

We do not usually offer financial support for internships in our group. It is hard to acquire the research background in our area and make meaningful contributions in a very short time to make this endeavor worthwhile. If you are interested in a longer-termed MS or Ph.D, then we are interested. But a three-month project is unlikely to be duly productive, at least in our area of research.

That being said, it is important to know what not to do when applying for a position.

#### RULE

1. Please respect the professor’s time and keep your emails short (no more than a screenful, 10-15 lines). While it is natural for you to take pride in your accomplishments, we get so many emails every day that long ones automatically get filtered out. If you feel your case is strengthened by a resume, attach a word document.

2. Do not pad your resume with unnecessary information (athletic prowess, GRE scores, work habits, debate societies, etc). Once again, long emails (sometimes even from our colleagues!) get automatically ignored. Stick to your strong points as a student (GPA, research background, interests and goals, internships). Keep it short and do not dilute it with irrelevant details (there is a time and a place for that, and this email is not it).

3. Do NOT ask professors for research positions in areas unrelated to them. For instance, do not ask me for research options in signal processing or VLSI or communications. If you cannot even be bothered to spend ten minutes researching my area, there’s no way you will convince me you are going to do any actual work during your stay here! It is tempting to reduce effort on your side by spamming professors en masse, but this ultimately indicates a lack of sincerity that is unlikely to be rewarded. In fact, spam emails are frowned upon very seriously in most departments, and could hurt your chances by getting you blacklisted.

4. Finally, while we are willing to help, please do not request us to circulate your letter or suggest names. It is hard for us to find time to deal with personal requests such as these.

Bottomline – keep your letter concise and make it relevant. Do not use a common template and start spamming professors. You will be surprised at how easy it is to distinguish between a custom-letter and a genuine one! Most importantly, do your homework and do not expect others to do this for you. As long as your email sounds sincere, and demonstrates genuineness on your part, we are willing to help.

Perhaps the most effective advice for prospective students is from Prof. David Evans at UVA. I enclose the link below. I think most of us agree with his assessment!