Near-Field Modulation of Differently Oriented Single Photon Emitters with A Plasmonic Probe

Abstract

Single photon emitters (SPEs) are critical components of photon-based quantum technology. Recently, the interaction between surface plasmons and emitters has attracted increasing attention because of its potential to improve the quality of single-photon sources through stronger light−matter interactions. In this work, we use a hybrid plasmonic probe composed of a fiber taper and silver nanowire to controllably modulate the radiation properties of SPEs with differently oriented polarization. For out-of-plane oriented SPEs such as single CdSe quantum dots, the radiation lifetime could be reduced by a factor as large as seven; for in-plane oriented SPEs such as hBN defect SPEs, the average modulation amplitude varied from 0.69 to 1.23, depending on the position of the probe. The experimental results were highly consistent with the simulations and theory. This work provides an efficient approach for optimizing the properties of SPEs for quantum photonic integration.

Tunable Single-Photon Emission with Wafer-Scale Plasmonic Array

“…Considerable efforts have been devoted to realize controllable SPE brightness and lifetime via nanofabrication, development of synthetic emitters, and defects engineering. − One of the most promising routes is based on plasmonic effects by heterogeneous integration with metallic nanostructures . An array of nanoantennae with wafer-scale uniformity enables coupling between plasmonic surface resonance states and defect levels in h-BN, , which leads to a decrease of the SPE radiative lifetime and, thereby, an increase of the zero-phonon line (ZPL) intensity of the SPE. − ,− The SPE enhancement is highly sensitive to the quality and control of the plasmonic array because it depends on the coupling between the SPE and plasmonic array, as well as the contamination introduced in the heterogeneous integration process. − Most reported studies adopted top-down fabrication on the basis of evaporated metals because the process is relatively simple and robust in size control of designed patterns. For conventional plasmonic nanostructures with high field enhancement, , larger optical losses commonly appear because of scattering among electrons by defects and grain boundaries formed in individual and nanosized metals.…”

Coupling of Photon Emitters in Monolayer WS2 with a Photonic Waveguide Based on Bound States in the Continuum

“…SPEs have been investigated in various material systems, including quantum dots, 20−22 carbon nanotubes, 23,24 crystal color centers, 25,26 two-dimensional (2D) materials. 21,27 Among them, 2D materials are particularly appealing for large-scale integration and applications because they can be easily transferred and placed. 28−32 They have mechanical flexibility and are atomically thin compared with other systems, 27,33 allowing emitters to achieve a high extraction efficiency without total internal reflection.…”

“…Single-photon emitters (SPEs) are the central building blocks for quantum PICs. SPEs have been investigated in various material systems, including quantum dots, − carbon nanotubes, , crystal color centers, , two-dimensional (2D) materials. , Among them, 2D materials are particularly appealing for large-scale integration and applications because they can be easily transferred and placed. − They have mechanical flexibility and are atomically thin compared with other systems, , allowing emitters to achieve a high extraction efficiency without total internal reflection. − However, to meet the demand for high refractive index contrast in optical waveguides, high-quality fabrication processes are required to pattern PICs on high-refractive-index substrates, which are usually very costly. For example, PICs based on silicon nitride require a well-controlled etch depth and smooth sidewall to achieve a minimum transmission loss of 1–2 dB/cm .…”