title: Quantum-correlated two-photon transitions to excitons in semiconductor quantum wells.
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.
authors.affiliation: Physics Department, Universidad de los Andes, A.A. 4976, Bogotá D.C., Colombia.
authors.forename: L J
authors.initials: LJ
authors.lastname: Salazar
authors.forename: D A
authors.initials: DA
authors.lastname: Guzmán
authors.forename: F J
authors.initials: FJ
authors.lastname: Rodríguez
authors.forename: L
authors.initials: L
authors.lastname: Quiroga