This Letter reports the design, fabrication, and evaluation of reflection-type planar vapor cells for chip-scale atomic clocks. The cell with 2–8 mm cavity length contains two 45◦ Bragg reflector mirrors assembled using a local anodic bonding. Coherent population trapping resonance of Rb atoms is observed, realizing an atomic clock operation. Allan deviations at an averaging time of 1 s are 2.2 × 10−10 and 9.5 × 10−11 for 2 mm long and 6 mm long vapor cells, respectively. These results show that planar vapor cells compatible with a system-in-package are feasible without degradation of clock stabilities compared to conventional vertically stacked cells.
|Number of pages||4|
|Publication status||Published - 2021 May 15|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics