Cold Atoms and Quantum Optics

Cold atoms science has been blooming first with the Nobel prize assigned to Chu, Phillips and Cohen-Tannoudji in 1997 (methods to cool and trap atoms), then with a second one assigned in 2001 to Cornell, Wieman and Ketterle (Production and studies of Bose-Einstein Condensate), and – more recently – with the developments of increasingly precise optical atomic clocks, a first wave of quantum-based devices like gravity meters and the prospective of quantum computing and quantum encrypted communication.​

Coherent participates in this application as a supplier of powerful single-frequency lasers (Mephisto MOPA) used to build all-optical cold atom traps. Unique combination of ultra-narrow linewidth and extreme phase and intensity stability of these lasers enables lowest atom heating rates in optical dipoles or optical lattices used to study phase transitions, quantum simulators or cold diatomic molecules. In addition, Coherent femtosecond lasers like Chameleon and Mira with their OPOs are used to produce photon pairs in entanglement experiments. CW laser diodes at 405 nm are also used to demonstrate quantum key distribution in quantum encryption experiments, while passively stabilized diodes are used to cool atoms when MHz-class linewidth and accuracy is sufficient like in Rubidium traps.​