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arXiv · 0711.4172

Broadband optical delay with large dynamic range using atomic dispersion

M. R. Vanner·R. J. McLean·A. I. Sidorov·P. Hannaford·A. M. Akulshin
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Abstract

We report on a tunable all-optical delay line for pulses with optical frequency within the Rb $D_2$ absorption line. Using frequency tuning between absorption components from different isotopes, pulses of 10 ns duration are delayed in a 10 cm hot vapour cell by up to 40 ns while the transmission remains above 10%. The use of two isotopes allows the delay to be increased or decreased by optical pumping with a second laser, producing rapid tuning over a range of more than 40% of the initial delay at 110$^{\circ}$C. We investigate the frequency and intensity ranges in which this delay line can be realised. Our observations are in good agreement with a numerical model of the system.

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M. R. Vanner, R. J. McLean, A. I. Sidorov, P. Hannaford, A. M. Akulshin. 2008-04-26. Broadband optical delay with large dynamic range using atomic dispersion. https://doi.org/10.1088/0953-4075/41/5/051004

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