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arXiv · 1109.6895

Quantum-correlated two-photon transitions to excitons in semiconductor quantum wells

L. J. Salazar·D. A. Guzmán·F. J. Rodríguez·L. Quiroga
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Abstract

The dependence of the excitonic two-photon absorption on the quantum correlations (entanglement) of exciting biphotons by a semiconductor quantum well is studied. We show that entangled photon absorption can display very unusual features depending on space-time-polarization biphoton parameters and absorber density of states for both bound exciton states as well as for unbound electron-hole pairs. We report on the connection between biphoton entanglement, as quantified by the Schmidt number, and absorption by a semiconductor quantum well. Comparison between frequency-anti-correlated, unentangled and frequency-correlated biphoton absorption is addressed. We found that exciton oscillator strengths are highly increased when photons arrive almost simultaneously in an entangled state. Two-photon-absorption becomes a highly sensitive probe of photon quantum correlations when narrow semiconductor quantum wells are used as two-photon absorbers.

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L. J. Salazar, D. A. Guzmán, F. J. Rodríguez, L. Quiroga. 2011-09-30. Quantum-correlated two-photon transitions to excitons in semiconductor quantum wells. https://doi.org/10.1364/oe.20.004470

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