Transient four-wave mixing signals were observed in cold sodium atoms. This phenomenon is interpreted as Bragg diffraction of a probe pulse by a population grating of the ground-state hyperfine level induced by pump pulses. The decay time of this grating is directly related to the temperature of the cold atoms and can serve as a novel technique for temperature diagnostics.
© 1998 Optical Society of America
Masaharu Mitsunaga, Makoto Yamashita, Masato Koashi, and Nobuyuki Imoto, "Temperature diagnostics for cold sodium atoms by transient four-wave mixing," Opt. Lett. 23, 840-842 (1998)