Chinese Optics Letters

Frequency-locked tunable LD laser with a broad bandwidth

常宏, 武海斌, 谢常德, 王海

Published Jan 1, 2004• 0 citations

Abstract

Using lock-in amplifer and proportional, integral, and derivative (PID) electric circuit, the frequency of diode laser is stabilized on a highly mechanical stable Fabry-Perot (FP) cavity transmission peak. When the frequency locking system is on, the frequency tunable range of the laser is about 4GHz around the D1 transition of Rb. The laser frequency tuning is implemented by scanning the FP cavity length. The fluctuation of frequency of the output laser is less than 1MHz, and the drift of the center frequency is less than 1.5MHz in 1.5min. This system has great potential of the application in the experimental investigation of the interaction between light and atoms, especially, for the case of far off the atomic resonance.

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