Atomic Spectroscopy with Squeezed Light for Sensitivity Beyond the Vacuum-State Limit

摘要: A frequency tunable source of squeezed light has been developed which is suitable for a variety spectroscopic applications. In initial experiments continuous tunability over range 2 GHz achieved with directly observed nonclassical noise reduction 6 dB relative to the vacuum-state limit in balanced homodyne detector. process light-induced absorption nonlinear crystal identified as principal loss mechanism prevents observation yet larger degrees squeezing. Although our potentially broadly wavelengths from 840 970 nm, current research centers on performance at 852 nm spectroscopy D 2 line atomic cesium. For frequency-modulated (FM) saturation vapor cell, an improvement 3.1 sensitivity usual quantum demonstrated detection Doppler-free resonances. When corrected thermal detector, enhancement signal-to-noise ratio brought by field 3.8 shot-noise set vacuum fluctuations probe field.