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arXiv · 1204.4131

Avalanche amplification of a single exciton in a semiconductor nanowire

Gabriele Bulgarini·Michael E. Reimer·Moïra Hocevar·Erik P. A. M. Bakkers·Leo P. Kouwenhoven·Val Zwiller
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Abstract

Interfacing single photons and electrons is a crucial ingredient for sharing quantum information between remote solid-state qubits. Semiconductor nanowires offer the unique possibility to combine optical quantum dots with avalanche photodiodes, thus enabling the conversion of an incoming single photon into a macroscopic current for efficient electrical detection. Currently, millions of excitation events are required to perform electrical read-out of an exciton qubit state. Here we demonstrate multiplication of carriers from only a single exciton generated in a quantum dot after tunneling into a nanowire avalanche photodiode. Due to the large amplification of both electrons and holes (> 10^4), we reduce by four orders of magnitude the number of excitation events required to electrically detect a single exciton generated in a quantum dot. This work represents a significant step towards single-shot electrical read-out and offers a new functionality for on-chip quantum information circuits.

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Gabriele Bulgarini, Michael E. Reimer, Moïra Hocevar, Erik P. A. M. Bakkers, Leo P. Kouwenhoven, Val Zwiller. 2012-04-18. Avalanche amplification of a single exciton in a semiconductor nanowire. https://doi.org/10.1038/nphoton.2012.110

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