Brief Communications

Temporal coherence of the radiation emitted by injection lasers

B. S. Vvedenskii, A. S. Logginov, K. S. Senatorov


Abstract: A modified Michelson interferometer was used to investigate the temporal coherence of the radiation emitted from injection lasers with single- and double-sided heterojunctions. The lasers were operated in the pulsed regime at room and liquid-nitrogen temperatures. The coherence length for the single-mode emission was 8–30 mm at 300°K and below 30–45 mm at 77°K. The use of the apparatus as an intensity interferometer yielded the autocorrelation function of the field and the corresponding function of the intensity of the laser radiation. A comparison of these two autocorrelation functions indicated that the spectral broadening of a single mode was primarily due to phase fluctuations.

UDC: 621.378

PACS: 42.55.Px, 42.60.Jf, 42.25.Kb, 07.60.Ly

Received: 26.12.1973

 English version: Soviet Journal of Quantum Electronics, 1974, 4:5, 678–679