Investigation of coherent population trapping signals in 87Rb cells with buffer gas

Characteristics of CPT (coherent population trapping) signal are investigated in small-size glass vapor cells containing Rb-87 and Ne buffer gas with narrow linewidth laser pumping on D-2 line. Parameters of CPT absorption signals are measured using small-size vapor cells with Ne buffer gas pressure in range of 200-400 Torr, cell temperature in range of 65-120 degrees C and values of laser pumping power of 30-400 mu W/cm(2). Optimum conditions, under which the minimal value of short-term instability of resonance line is achieved, are obtained in experiments. CPT signals using vapor cells based on integrated technologies containing Rb-87 in atmosphere of Ne are also investigated. The CPT signals with typical linewidths of 2-3 kHz and signal-to-noise ratio of 1500 in 1 Hz bandwidth are observed, which allows one to provide relative frequency instability of 10(-11) at 100 s.