Saturated absorption spectroscopy with a Zeeman shift

Recently a new type of spectroscopy using Zeeman shift has been developed, which aims for a large recapture range by making a dispersive-like signal obtained from the subtraction of two different circularly polarized Doppler-broadened absorption signals in the presence of a magnetic field (order of 100 G). We would like to propose another method for stabilizing a diode laser frequency onto an atomic frequency with a small tunable range in the presence of small longitudinal magnetic field (order of Gauss). A solid state diode laser is preferred as it is a good light source. Our technique has the advantages of cancellation of frequency fluctuation over side-locking and no need for phase-sensitive detection and frequency modulation over peak-locking. A subtracted SAS signal and the blocking signal are displayed on one photodiode.