Coherent population trapping in small- and chip-scale 87Rb vapor cells with buffer gas
The characteristics of coherent population trapping (CPT) signal were investigated in small-size glass vapor cells containing [Formula: see text]Rb and Ne buffer gas with narrow line-width laser pumping on D2 line. The parameters of CPT signals were measured using small-size vapor cells with Ne buffer gas pressure in the range of 200–400 Torr, cell temperature in the range of 65–120 [Formula: see text]C and the values of laser pumping power of 30–400 [Formula: see text]W/cm2. Optimal conditions, under which the minimal value of short-term instability of resonance line is achieved, were obtained in experiments. Orientation frequency shifts of CPT resonance using glass [Formula: see text]Rb vapor cells containing buffer gas and anti-relaxation coating were compared. CPT signals using vapor cells based on integrated technologies containing [Formula: see text]Rb in atmosphere of Ne were also investigated. The CPT signals with typical line widths 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[Formula: see text] at 100 s.