|
research
|
| | | |
| |
Caltech
I work in the lab of Prof. Hideo Mabuchi at Caltech, although Prof. Mabuchi has moved, with most of the group, to Stanford. Our group's title is "Physical Measurement and Control". In particular, we study applications of engineering methodologies to physics, especially control and dynamical systems theory.
My thesis research involves developing simple, approximate models for quantum systems. The difficulty of exact simulation of quantum systems scales exponentially, and simple models will be necessary in order to have a chance to implement real-time feedback control. In a little more detail, I use a technique called "proper orthogonal decomposition" to algorithmically derive small, linear spaces in which the current best guess of the density matrix propagates. This allows up to get a good approximation while carrying forward fewer than 20 variables, independent of the size of the system. I am currently working on implementing a control algorithm (all in simulation) to show that we can lengthen the time a bistable state stays in each of its two stable configurations.
One of my earlier research projects revolved around applications of "atom chips". Ben Lev, a senior student in our lab, developed a set of techniques for creating magnetic and magneto-optical traps using magnetic fields generated from currents flowing on micro-fabricated chips. I am extending this work to a new magneto-electrostatic ring trap. The paper proposing this trapping technique is in the list of references below, as are three papers that Ben has written. Two are related to fabrication and atom mirrors; the other is the proposal paper for the photonic bandgap cavity work that I may work with after I demonstrate the magneto-electrostatic traps.
| |
| | | |
| | | |
| |
Los Alamos
Before coming to Caltech, I worked with Dr. Salman Habib in Group T-8 at Los Alamos National Laboratory for a year. In addition to managing the group Linux network, I worked on the quantum mechanics of nanomechanical devices and a bit on cosmology. Kurt Jacobs, Keith Schwab, Salman and I wrote a paper proposing feedback cooling of nanomechanical oscillators as a way of getting to the quantum regime. Keith's experimental group is getting close to being able to demonstrate this technique in the laboratory.
| |
| | | |
| | | |
| |
References
A. Hopkins, B. Lev, H. Mabuchi,
"Proposed magneto-electrostatic ring trap for neutral atoms," Phys. Rev. A 70, 053616 (2004). PDF
A. Hopkins, K. Jacobs, S. Habib, and K.
Schwab, "Feedback cooling of a nanomechanical resonator," Phys.
Rev. B, 68, 235328 (2003) PDF
| |
| | | |
|
|
|
