A New Architecture for Miniaturization of Atomic Clocks Exploiting a Piezoelectric-Thin-Film Vibration From a rack-mount system toward a microchip | Tokyo Tech News | Tokyo Institute of Technology
Atomic Clock - SPX-14830 - SparkFun Electronics
ALANO DCF77 77kHz NIST Radio Controlled Clock Modules, 30dB High Gain Atomic Clock Receiver Module, 100mm Antenna 1.2 to 5V Operating Voltage for Radio/Radio Alarm Clock/Timer: Amazon.co.uk: Electronics & Photo
Miniature Atomic Clock (MAC - SA5X) is only 2 x 2" - Electronics-Lab.com
Atomic Pinball Clock | Hackaday
Commercial space Chip Scale Atomic Clock module is radiation tolerant
Chip-Level-Integrated Frequency Standards | National Institute of Information and Communications Technology