A slotted photonic crystal cavity structure on an optical nanofiber is proposed to realize cavity quantum electrodynamics. The device has a Q-factor of ∼ 1100 and excellent single photon coupling to the nanofiber fundamental mode.
We propose a single-sided optical nanofiber cavity (SSONFC) to facilitate cavity quantum electrodynamics (cQED). The structure is designed and analyzed throughs finite-difference time-domain simulations. A systematic evaluation of the cavity properties and spontaneous emission characteristics has been conducted. Our findings demonstrate that this design significantly enhances the spontaneous emission rate of a single quantum emitter (SQE). A Purcell factor of ∼22 and a maximum unidirectional single-photon coupling efficiency of around 72% into the ONF’s guided mode can be achieved when an SQE is positioned on the SSONFC surface. Additionally, a high scattering limited quality factor (Q∼2510) is obtained for the fundamental cavity mode. The structure’s dimensions can be adjusted to accommodate different SQE emission wavelengths, making it a versatile solution. This fiberintegrated single-photon device holds potential for applications in quantum phase switches, and single-photon transistors.
We demonstrate cavity QED conditions in the Purcell regime for single quantum emitters on the surface of an optical nanofiber. The cavity is formed by combining an optical nanofiber and a nanofabricated grating to create a composite photonic crystal cavity. By using this technique, significant enhancement of the spontaneous emission rate into the nanofiber guided modes is observed for single quantum dots. Our results pave the way for enhanced on-fiber light-matter interfaces with clear applications to quantum networks.
Optical nanofibers provide a versatile platform for exploring strong light-matter interactions at the single-quantum level, a central goal of quantum optics. Their subwavelength diameter supports tightly confined guided modes with strong evanescent fields, enabling efficient coupling between photons and nearby atoms. By incorporating fiber Bragg gratings, nanofibers can form fully fiber-integrated high-finesse cavities, combining strong atom-photon coupling with efficient and low-loss optical input-output interfacing in the setting of cavity quantum electrodynamics (QED). In parallel, nanofiber systems naturally realize waveguide QED, where atoms interact strongly with propagating photons in a one-dimensional geometry. In this review, we introduce the underlying physical principles, summarize key experimental techniques and representative phenomena, and discuss prospects for applications in quantum information processing, quantum networks, and related quantum technologies.