Intra-stark relaxation of Nd sup 3+ in silicate glass: Subpicosecond accumulated photon echo experiments

We have directly measured in the time domain the rates of phonon-induced population relaxation within the {sup 4}G{sub 5/2}, {sup 2}G{sub 7/2} Stark manifold of Nd{sup 3+} in a silicate glass. At 13 K, these processes occur in the picosecond to subpicosecond time regime. The populations relaxation time increases with excitation frequency within each inhomogeneously broadened Stark component. Finally, the location of the Stark components within the entire inhomogeneous profile can be inferred from the data. 13 refs., 1 fig

Temperature-Dependent Dephasing of Delocalized Dimer States of Pentacene in p-Terphenyl: Picosecond Photon Echo Experiments

Optical dephasing of pentacene dimers in p-terphenyl is studied. Dimer states R3 and R4 exhibit an exponential temperature activation of T2' which is inconsistent with a mechanism involving scattering between delocalized dimer states. Other dephasing mechanisms are discussed. An upper limit is placed on the relaxation rate from the upper dimer state, R1, to R3

Resonant and off-resonant transients in electromagnetically induced transparency: turn-on and turn-off dynamics

This paper presents a wide-ranging theoretical and experimental study of nonadiabatic transient phenomena in a Lambda electromagnetically induced transparency system when a strong coupling field is rapidly switched on or off. The theoretical treatment uses a Laplace transform approach to solve the time-dependent density matrix equation. The experiments are carried out in a 87/Rb magneto-optical trap. The results show transient probe gain in parameter regions not previously studied, and provide insight into the transition dynamics between bare and dressed states