High-selectivity quantum pulse gating of photonic temporal modes using all-optical Ramsey interferometry

TLDR

Temporal modes are broadband, field‑orthogonal wave‑packet states that enable high‑dimensional encoding, but practical deployment requires a highly selective quantum pulse gate that can route photonic packets with high temporal‑mode discrimination and efficiency. Here, we present the first implementation of a highly selective quantum pulse gate. The gate is realized by a generalization of all‑optical Ramsey interferometry, termed temporal‑mode interferometry, which extends the technique from continuous‑wave fields to broadband temporal modes. Reference: Phys.

Abstract

Temporal modes (TMs) are field-orthogonal broadband wave-packet states of light occupying a common frequency band, and they can encode information in a higher-dimensional alphabet compared to, say, photon polarization. The key—yet still missing—ingredient for the full implementation of a system deploying TMs is a highly selective quantum pulse gate—a multiplexing device that can route photonic packets according to their temporal shape with high temporal-mode discrimination and high efficiency, figures of merit that together we call high selectivity. Here, we present the first implementation of a highly selective quantum pulse gate. The method is a generalization of all-optical Ramsey interferometry, so far demonstrated only for continuous-wave light fields [Phys. Rev. Lett.117, 223601 (2016)PRLTAO0031-900710.1103/PhysRevLett.117.223601]. As applied to temporal modes, we refer to the method as temporal-mode interferometry.