Southwest Quantum Information and Technology

Progress towards chip-scale transverse laser cooling of thermal atomic beams

Presenting Author: Chao Li, Georgia Institute of Technology
Contributing Author(s): Ardalan Lotfi, Farrokh Ayazi, Chandra Raman

We present progress toward on-chip laser cooling of thermal rubidium atomic beams in an integrated platform using MEMS collimators and mirrors. A thin silicon capillary array tailors the transverse velocity distribution of thermal atoms into the capture range of laser cooling within a few millimeters. Immediately then, we use micromirrors to precisely overlap a strong elliptical standing wave (e.g., 0.2 mm x 5 mm), i.e., the stimulated blue molasses, with the atomic beam sheet. As a result, transverse velocity spread can fall in the range of 1 m/s within the sub-centimeter travel distance. Furthermore, such an on-chip approach achieves high light intensity with relatively low laser power consumption due to the needed small cross-section area for miniatured atomic beams. So far, we have fabricated silicon collimators, performed stringent tests over the micromirrors’ resistance to alkali attack, and implemented Doppler-sensitive Raman spectroscopy to diagnose the transverse velocity distribution thoroughly. This on-chip hybrid of passive and active collimation paves the way towards a high-brightness atomic beam source that can find its applications in making compact atomic instruments, such as portable atomic beam-based clocks and gyroscopes.

(Session 5 : Thursday from 12:00pm-2:00 pm)