Decay of stationary light pulses in ultracold atoms

standing-wave electromagnetically induced transparency. We rely on full numerical solutions of the Maxwell-
Liouville equations without invoking secular and adiabatic approximations and arbitrary initial state assumptions.
These approximations and assumptions can conceal, e.g., significant loss and diffusion responsible for the decay
of stationary light pulses in cold atomic samples. The complex decay dynamics of a stationary light pulse is
here analyzed in terms of higher-order spin and optical coherences that arise from nonlinear interactions of the
stationary light pulse with the two counterpropagating components of a standing-wave driving field. Specific
results for stationary light pulses in cold 87Rb atoms have been discussed for temperature regimes where the
residual Doppler broadening is negligible.