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arXiv · 1109.4392

Laser spectroscopy of individual quantum dots charged with a single hole

B. D. Gerardot·R. J. Barbour·D. Brunner·P. A. Dalgarno·A. Badolato·N. Stoltz·P. M. Petroff·J. Houel·R. J. Warburton
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Abstract

We characterize the positively charged exciton (X1+) in single InGaAs quantum dots using resonant laser spectroscopy. Three samples with different dopant species (Be or C as acceptors, Si as a donor) are compared. The p-doped samples exhibit larger inhomogeneous broadening (x3) and smaller absorption contrast (x10) than the n-doped sample. For X1+ in the Be-doped sample, a dot dependent non-linear Fano effect is observed, demonstrating coupling to degenerate continuum states. However, for the C-doped sample the X1+ lineshape and saturation broadening follows isolated atomic transition behaviour. This C-doped device structure is useful for single hole spin initialization, manipulation, and measurement.

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B. D. Gerardot, R. J. Barbour, D. Brunner, P. A. Dalgarno, A. Badolato, N. Stoltz, P. M. Petroff, J. Houel, R. J. Warburton. 2011-09-20. Laser spectroscopy of individual quantum dots charged with a single hole. https://doi.org/10.1063/1.3665951

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