Optimization of frequency modulation transfer spectroscopy on the calcium 41S0 to 41P1 transition

We present experimental results of frequency modulation transfer spectroscopy in a vapor of neutral atomic calcium. The observed line shapes agree well with the theoretical model. We use numerical calculations in order to improve the signal shape such that its magnitude and its slope at the zero-crossing is maximized. When optimized this way, the frequency modulation transfer signal can be used for the sensitive optical detection of rare species or isotopes, Doppler-free frequency measurements or as a sensitive error signal for laser frequency stabilization. PACS 42.62.Fi; 32.70.Jz; 39.30.+w