cavity

The quantum speed limit describes the maximum rate at which a quantum system, here the quantized field of the optical cavity, can transition from one state to another. Now, Luis Orozco’s group at JQI, in collaboration with researchers from Shanxi University, China and Los Alamos National Laboratory have studied how fast a photon trapped inside of a cavity settled as they varied its coupling to a reservoir of laser-cooled atoms. The results were published recently in the journal Physical Review Letters, and show that the atomic environment could provide a speed-up in the time it took for the system to reach equilibrium.

Color is strange, mainly due to perception. Setting aside complex brain processes, what we see is the result of light absorption, emission, and reflection. Trees appear green because atoms inside the leaves are emitting and/or reflecting green photons. Semiconductor LED brake lights emit single color light when electrical current passes through the devices.