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arXiv · 1506.06379

Modeling and analysis of an ultra-stable subluminal laser

Zifan Zhou·Joshua Yablon·Minchuan Zhou·Ye Wang·Alexander Heifetz·Selim M. Shahriar
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Abstract

We describe a subluminal laser which is extremely stable against perturbations. It makes use of a composite gain spectrum consisting of a broad background along with a narrow peak. The stability of the laser, defined as the change in frequency as a function of a change in the cavity length, is enhanced by a factor given by the group index, which can be as high as 105 for experimentally realizable parameters. We also show that the fundamental linewidth of such a laser is expected to be smaller by the same factor. We first present an analysis where the gain profile is modeled as a superposition of two Lorentzian functions. We then present a numerical study based on a physical scheme for realizing the composite gain profile. In this scheme, the broad gain is produced by a high pressure buffer-gas loaded cell of rubidium vapor. The narrow gain is produced by using a Raman pump in a second rubidium vapor cell, where optical pumping is used to produce a Raman population inversion. We show close agreement between the idealized model and the explicit model. A subluminal laser of this type may prove to be useful for many applications.

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Zifan Zhou, Joshua Yablon, Minchuan Zhou, Ye Wang, Alexander Heifetz, Selim M. Shahriar. 2015-06-21. Modeling and analysis of an ultra-stable subluminal laser. https://doi.org/10.1016/j.optcom.2015.09.007

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