We present an experimental study of slow and stored light in Rb vapor cells under conditions of electromagnetically induced transparency (EIT). We study the fundamental limitations for pulse delay in such a system.
Preliminary results from an experimental study of slow light in anti-relaxation-coated Rb vapour cells are presented, and the construction and testing of such cells are described. The slow ground state decoherence rate allowed by coated cell walls leads to a dual-structured electromagnetically induced transparency (EIT) spectrum with a very narrow (< 100 Hz) transparency peak on top of a broad pedestal. Such dual-structured EIT permits optical probe pulses to propagate with greatly reduced group velocity on two time scales. Ongoing efforts to optimize the pulse delay in such coated cell systems are discussed.
Alkali vapor cells with antirelaxation coated walls can have long atomic coherence times. However, using such coated cells in the hyperfine configuration for electromagnetically induced transparency (EIT) requires longitudinal atomic motion to be confined to less than the hyperfine wavelength. We employed a narrow (1 mm) coated cell geometry to study hyperfine EIT and slow and stored light in warm R87b vapor, with results comparable to those in buffer gas cells and showing the promise of such cells for several applications.