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High-Rate Entanglement Source via Two-Photon Emission from Semiconductor Quantum Wells

Alex Hayat·Pavel Ginzburg·Meir Orenstein
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Abstract

We propose a compact high-intensity room-temperature source of entangled photons based on the efficient second-order process of two-photon spontaneous emission from electrically-pumped semiconductor quantum wells in a photonic microcavity. Two-photon emission rate in room-temperature semiconductor devices is determined solely by the carrier density, regardless of the residual one-photon emission. The microcavity selects two-photon emission for a specific signal and idler wavelengths and at a preferred direction without modifying the overall rate. Pair-generation rate in GaAs/AlGaAs quantum well structure is estimated using a 14-band model to be 3 orders of magnitude higher than for traditional broadband parametric down-conversion sources.

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Alex Hayat, Pavel Ginzburg, Meir Orenstein. 2007-05-17. High-Rate Entanglement Source via Two-Photon Emission from Semiconductor Quantum Wells. https://doi.org/10.1103/physrevb.76.035339

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