Department of Physics & Astronomy
University of New Mexico

CQuIC Seminars

Coherent Matter Wave Circuits for Atomtronics

Presented by Malcolm Boshier, Los Alamos National Laboratory

The emerging field of atomtronics seeks to build atomic circuits in which currents are formed by coherent matter waves flowing inside complex waveguide structures. One motivation for developing this technology is creating waveguide atom interferometers, since they could be made much smaller than their free-space counterparts. In this talk I will present our recent work with atomtronic circuits aimed towards this goal. The technology used in all of this work is the Painted Potential, a combination of two red-detuned optical dipole traps. A rapidly-moving tweezer beam "paints" a desired 2D potential on top of a static horizontal light sheet. BECs created in the resulting time-averaged trap can then be manipulated by adiabatically changing the potential. One of the first atomtronic circuit devices studied was the BEC analog of the Superconducting Quantum Interference Device (SQUID). Both rf and dc atom-SQUIDs have now been demonstrated. In our dc device, a BEC was created in a toroidal potential with two thin potential barriers. We observed that the barriers behaved as ideal Josephson Junctions. I will discuss this work and our progress towards observing quantum interference in the atom-SQUID.
The Painted Potential can also realize and integrate the basic elements needed to create complex matter wave circuits. Tilting a waveguide containing a BEC will accelerate it to a desired velocity. We have propagated these moving condensates around bends connecting straight waveguides, around closed waveguide loops, and through Y-junctions which can act as switches and coherent beamsplitters. I will present these results and discuss the challenges associated with ensuring single-mode propagation in atomtronic circuits.

3:30 pm, Thursday, May 4, 2017
PAIS-2540, PAIS

Disability NoticeIndividuals with disabilities who need an auxiliary aid or service to attend or participate in P&A events should contact the Physics Department (phone: 505-277-2616, email: physics@unm.edu) well in advance to ensure your needs are accomodated. Event handouts can be provided in alternative accessible formats upon request. Please contact the Physics front office if you need written information in an alternative format.

A schedule of talks within the Department of Physics and Astronomy is available on the P&A web site at http://physics.unm.edu/pandaweb/events/index.php