We investigate the use of resonant optical Raman pulses to excite and rephase ground state spin coherences via the partial storage or shelving of atoms. Unlike direct-rf-excited spin echoes or off-resonant Raman echoes, the resonant Raman optical field efficiently excites and rephases the spin coherence using p and 2p pulses, respectively. In a crystal of Pr doped Y2SiO5, we experimentally obse...

The phase noise of quantum dot lasers is investigated theoretically by coupling the Langevin noise sources into the rate equations. The off-resonant populations in the excited state and in the carrier reservoir contribute to the phase noise of ground-state emission lasers through the phase-amplitude coupling effect. This effect arises from the optical-noise induced carrier fluctuations in the o...

Two-photon collisions at electron positron storage rings are a good laboratory to investigate the properties of meson resonances and play a crucial role in glueball searches. A resonant state R can be formed by the collision of two photons via the reaction e+e− → e+e−R (fig. 1). The outgoing electron and positron are usually scattered at very small angles and are not detected (no-tag mode). In ...