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Quantum 2.0 Conference and Exhibition

Quantum interference between photons from two waveguide-integrated tin-vacancy centers

Alexander M. Stramma, Christopher Waas, Hans K. C. Beukers, Timo Dolné, Nina Codreanu, Niv Bharos, Julia M. Brevoord, Tim Turan, Pepijn Habing, Ronald Hanson

Published Jan 1, 2025• 0 citations
Publisher

Abstract

Quantum networks are based on shared remote entanglement between local nodes by exchanging indistinguishable photons. We show Two-Photon Quantum Interference between tin-vacancy centers in diamond-waveguides and report on the progress towards remote entanglement generation.
DOI
10.1364/quantum.2025.qth2b.2

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We demonstrate quantum interference between indistinguishable photons emitted by two nitrogen-vacancy centers in distinct diamond samples separated by two meters. Macroscopic solid immersion lenses are used to enhance photon collection efficiency. Quantum interference is verified by measuring a value of the second-order cross-correlation function g((2))(0)=0.35±0.04<0.5. In addition, optical transition frequencies of two separated nitrogen-vacancy centers are tuned into resonance with each other by applying external electric fields. An extension of the present approach to generate entanglement of remote solid-state qubits is discussed.