Showing papers by "Edward S. Fry published in 1996"
TL;DR: Continuous wave (cw) amplification and laser oscillation without population inversion have been observed for the first time in a L scheme within the sodiumD1 line.
Abstract: Continuous wave (cw) amplification and laser oscillation without population inversion have been observed for the first time in a $\ensuremath{\Lambda}$ scheme within the sodium ${D}_{1}$ line. This is also the first demonstration in which the lasing medium was an atomic beam; this is an approach which, in addition to elucidating the physics, lays a foundation for extensions into the ultraviolet. Calculations using realistic atomic structure were critical to the choice of experimental approach. Observations agree with full density-matrix calculations and clearly show there was no population inversion.
208 citations
10 May 1996
TL;DR: In this article, two experiments in which laser oscillation without population inversion was obtained for the first time are reported, and analytical solutions are presented to elucidate the principles of the experiments.
Abstract: Two experiments in which laser oscillation without population inversion was obtained for the first time are reported. Analytical solutions are presented to elucidate the principles of the experiments. Numerical simulations and experimental results in a Rb vapor cell and a Na atomic beam for the gain profile are compared.
4 citations
TL;DR: Ramsey fringes in the absorption line shape for a weak optical field probing the transition between an unperturbed quantum state and one that is dynamically Stark shifted by a strong pump field are observed.
Abstract: We observe Ramsey fringes in the absorption line shape for a weak optical field probing the transition between an unperturbed quantum state and one that is dynamically Stark shifted by a strong pump field. {copyright} {ital 1996 The American Physical Society.}
1 citations
01 Jan 1996
TL;DR: Lasing without inversion (LWI) as mentioned in this paper is a new tool in the quest for ultra-violet and X-ray laser physics, which overcomes a commonly accepted limitation for laser physics.
Abstract: Lasing without inversion (LWI) [1] opens new horizons for laser physics not only because it overcomes a commonly accepted limitation for lasers, but also because it provides a new tool in the quest for ultra-violet and X-ray lasers. As one moves towards higher frequencies of lasers, the rate of spontaneous emission grows as the third power of frequency, so the pumping power required to create inversion scales as the forth power of frequency. LWI significantly decreases pumping power requirements and allows lasing with much higher frequency to the ground state (since otherwise it is difficult to create inversion).