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Quantum 2.0 Conference and Exhibition

Cavity-Assisted highly efficient Atomic Frequency Comb solid-state Quantum Memory

Stefano Duranti, Sören Wengerowsky, Leo Feldmann, Alessandro Seri, Bernardo Casabone, Hugues de Riedmatten

Published Jan 1, 2023• 0 citations
Publisher

Abstract

We report a record high-efficiency a tomic f requency c omb q uantum m emory u sing a Pr3+ :Y2SiO5 crystal embedded in an impedance-matched cavity. We achieve an efficiency of 62 % for weak coherent pulses and 52 % for time-bin qubits
DOI
10.1364/quantum.2023.qw4b.3

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A light-storage experiment with a total (storage and retrieval) efficiency η=56% is carried out by enclosing a sample, with a single-pass absorption of 10%, in an impedance-matched cavity. The experiment is carried out using the atomic frequency comb (AFC) technique in a praseodymium-doped crystal (0.05%Pr(3+):Y2SiO5) and the cavity is created by depositing reflection coatings directly onto the crystal surfaces. The AFC technique has previously by far demonstrated the highest multimode capacity of all quantum memory concepts tested experimentally. We claim that the present work shows that it is realistic to create efficient, on-demand, long storage time AFC memories.