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Polarization instabilities in a two-photon laser

Olivier Pfister·William J. Brown·Michael D. Stenner·Daniel J. Gauthier
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Abstract

We describe the operating characteristics of a new type of quantum oscillator that is based on a two-photon stimulated emission process. This two-photon laser consists of spin-polarized and laser-driven $^{39}$K atoms placed in a high-finesse transverse-mode-degenerate optical resonator, and produces a beam with a power of $\sim $0.2 $μ$W at a wavelength of 770 nm. We observe complex dynamical instabilities of the state of polarization of the two-photon laser, which are made possible by the atomic Zeeman degeneracy. We conjecture that the laser could emit polarization-entangled twin beams if this degeneracy is lifted.

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Olivier Pfister, William J. Brown, Michael D. Stenner, Daniel J. Gauthier. 2001-03-21. Polarization instabilities in a two-photon laser. https://doi.org/10.1103/physrevlett.86.4512

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