Physica status solidi. C, Conferences and critical reviews/Physica status solidi. C, Current topics in solid state physics

Entangled photon pairs from a quantum dot source

R. M. Stevenson, Robert James Young, P. Atkinson, K. Cooper, D. A. Ritchie, Andrew J. Shields

Published Nov 22, 2006• 0 citations

Publisher

Abstract

Abstract We present the results of recent experiments designed to manipulate the splitting in quantum dots, to eradicate the which‐path information that prevents entangled photon emission. We demonstrate that dots with splitting within the homogeneous linewidth can be grown directly by carefully controlling the thickness of the dot layer. Polarization dependent correlation measurements on these dots show characteristic features of entanglement, only present for dots with small splitting. Our results indicate that for the first time, we have observed triggered entangled photon pair emission from a quantum dot. The ability to trigger the emission of just one photon pair has advantages over other schemes to generate entangled photons, including scalability of the applications. Finally, we note that the device, once optimized, could be implemented by a simple LED‐like structure. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

DOI: 10.1002/pssc.200671522

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