Quasi zero-background tunable diode laser absorption spectroscopy employing a balanced Michelson interferometer.
Tunable diode laser spectroscopy (TDLS) normally observes small fractional absorptive reductions in the light flux. We show, that instead a signal increase on a zero background can be obtained. A Michelson interferometer, which is initially balanced out in destructive interference, is perturbed by gas absorption in one of its arms. Both theoretical analysis and experimental demonstration show that the proposed zero-background TDLS can improve the achievable signal-to-noise ratio.
Guan
Zuguang
Z
Atomic Physics Division, Lund University, P.O. Box 118, S-221 00, Lund, Sweden.
Lewander
Märta
M
Svanberg
Sune
S