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arXiv · 0910.2292

Collimated blue light generated by four-wave mixing in Rb vapour

Alexander M. Akulshin·Russell J. McLean·Andrei I. Sidorov·Peter Hannaford
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Abstract

We investigate frequency up-conversion of low power cw resonant radiation in Rb vapour as a function of various experimental parameters. We present evidence that the process of four wave mixing is responsible for unidirectional blue light generation and that the phase matching conditions along a light-induced waveguide determine the direction and divergence of the blue light. Velocity-selective excitation to the 5D level via step-wise and two-photon processes results in a Doppler-free dependence on the frequency detuning of the applied laser fields from the respective dipole-allowed transitions. Possible schemes for ultraviolet generation are discussed.

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Alexander M. Akulshin, Russell J. McLean, Andrei I. Sidorov, Peter Hannaford. 2009-10-13. Collimated blue light generated by four-wave mixing in Rb vapour. https://doi.org/10.1364/oe.17.022861

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