Coherent perfect absorption of single photons in a fiber network

Abstract

Large distance implementation of quantum communication technologies requires coherent control of single photons in optical fiber networks. Here we demonstrate the phenomenon of coherent perfect absorption of single photons in a fully fiberized ultrathin plasmonic metamaterial fabricated at the end facet of an optical fiber. Continuous control of single-photon absorption probability is achieved by driving the network between the regimes of coherent total absorption and coherent total transmission. To circumvent phase fluctuations inherent to optical fiber networks, we implemented a reference-based postselection technique which yielded interference fringe visibility comparable to that of free space experiments. Coherent absorption of quantum light in fiber environment provides new opportunities for dissipative single-photon switching, filtering, and measurement, as well as for manipulation of entangled, weak coherent, and NOON states in optical fiber networks.

Single photon detection and manipulation in photonic integrated circuits

“…The unity system visibility is achievable if the device nonideality is mitigated. This result is close to the one demonstrated previously [141] with the exception that our phase stabilization method now enables us to control single-photon absorption probability on demand, which is crucial for utilizing the CPA phenomenon for quantum light processing. Next, we show how we used CPA for all-optical single-photon switching with a heralded single-photon source.…”

“…The probabilities to a detect a single photon at output ports C and D depend on the phase delay φ between the two optical paths due to interference on the second beamsplitter. The corresponding detection probabilities p c and p d are equal to [141] p c (φ ) = (1 + sin(φ ))/2,…”

“…The following quantum mechanical analysis briefly introduces the quantum regimes of coherent perfect absorption and transmission [141]. The quantum state of the photon in this analysis has the following path-entangled wave function…”

“…Recent achievements in fabrication of fully-fiberized metamaterial packages have made it possible to manipulate quantum light in fiber environment [272]. For instance, quantum coherent perfect absorption (CPA) with plasmonic metamaterial absorber, first demonstrated in free space [85], was shown in an optical fiber network [141]. In the latter experiment, an elaborate data postselection technique was used to overcome the effects of phase noise in optical fibers.…”

A generalized approach to quantum interference in lossy N-port devices via a singular value decomposition

“…Such "black box" approach facilitates a compact and efficient evaluation of quantum interference phenomena. In fact, these models successfully describe a variety of recent experiments, such as the anticoalescence of photons and nonlinear absorption [36,37], single-photon coherent perfect absorption [38][39][40] and coherent absorption of N00N states [41,42]. In addition, input-output theory of lossy beam splitters has inspired interesting theoretical proposals on nonlocal absorption [43] and quantum coherent absorption of squeezed light [44].…”