Single-shot high-resolution identification of discrete frequency modes of single-photon-level optical pulses

TL;DR

This paper introduces a high-resolution, single-shot method for identifying the frequency modes of single-photon-level optical pulses, enhancing quantum communication capabilities.

Contribution

The proposed scheme combines time-to-space and frequency-to-time mapping to identify frequency modes with high resolution even for unknown photon emission times.

Findings

Successfully mapped frequency modes to temporal modes for weak coherent pulses.

Achieved 100 MHz frequency interval mapping to 435 ns temporal intervals.

Potential to improve quantum repeater frequency multiplexing.

Abstract

Frequency-multiplexed quantum communication usually requires a single-shot identification of the frequency mode of a single photon . In this paper, we propose a scheme that can identify the frequency mode with high-resolution even for spontaneously emitted photons whose generation time is unknown, by combining the time-to-space and frequency-to-time mode mapping. We also demonstrate the mapping of the frequency mode (100 MHz intervals) to the temporal mode (435 ns intervals) for weak coherent pulses using atomic frequency combs. This frequency interval is close to the minimum frequency mode interval of the atomic frequency comb quantum memory with Pr3+ ion-doped Y2SiO5 crystal, and the proposed scheme has the potential to maximize the frequency multiplexing of the quantum repeater scheme with the memory.