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Interferometric Bell-state preparation using femtosecond-pulse-pumped Spontaneous Parametric Down-Conversion

Yoon-Ho Kim·Maria V. Chekhova·Sergei P. Kulik·Morton H. Rubin·Yanhua Shih
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Abstract

We present theoretical and experimental study of preparing maximally entangled two-photon polarization states, or Bell states, using femtosecond pulse pumped spontaneous parametric down-conversion (SPDC). First, we show how the inherent distinguishability in femtosecond pulse pumped type-II SPDC can be removed by using an interferometric technique without spectral and amplitude post-selection. We then analyze the recently introduced Bell state preparation scheme using type-I SPDC. Theoretically, both methods offer the same results, however, type-I SPDC provides experimentally superior methods of preparing Bell states in femtosecond pulse pumped SPDC. Such a pulsed source of highly entangled photon pairs is useful in quantum communications, quantum cryptography, quantum teleportation, etc.

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Yoon-Ho Kim, Maria V. Chekhova, Sergei P. Kulik, Morton H. Rubin, Yanhua Shih. 2001-03-30. Interferometric Bell-state preparation using femtosecond-pulse-pumped Spontaneous Parametric Down-Conversion. https://doi.org/10.1103/physreva.63.062301

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