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Contrast in transmission spectroscopy of a single quantum dot

B. D. Gerardot·S. Seidl·P. A. Dalgarno·M. Kroner·K. Karrai·A. Badolato·P. M. Petroff·R. J. Warburton
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Abstract

We perform transmission spectroscopy on single quantum dots and examine the effects of a resident carriers spin, the incident laser spot size, polarization, and power on the experimental contrast. We demonstrate a factor of 4 improvement in the maximum contrast by using a solid immersion lens to decrease the spot area. This increase yields a maximum signal to noise ratio of 2000 Hz-1/2, which will allow for MHz detection frequencies. We anticipate that this improvement will allow further investigation of spectral fluctuation and open up the feasibility for an all-optical read-out of an electron spin in a quantum dot.

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B. D. Gerardot, S. Seidl, P. A. Dalgarno, M. Kroner, K. Karrai, A. Badolato, P. M. Petroff, R. J. Warburton. 2007-01-25. Contrast in transmission spectroscopy of a single quantum dot. https://doi.org/10.1063/1.2743750

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