Fabrication of a centimeter-long cavity on a nanofiber for cavity quantum electrodynamics

Abstract

We report the fabrication of a 1.2 cm long cavity directly on a nanofiber using femtosecond laser ablation. The cavity modes with finesse values in the range of 200-400 can enable the "strong-coupling" regime of cavity QED, with high cooperativity of 10-20, for a single atom trapped 200 nm away from the fiber surface [Phys. Rev. A80, 053826 (2009)PLRAAN1050-294710.1103/PhysRevA.80.053826]. Such cavity modes can still maintain the transmission between 40%-60%, suggesting a one-pass intracavity transmission of 99.53%. Other cavity modes, which can enable cooperativity in the range of 3-10, show transmission over 60%-85% and are suitable for fiber-based single-photon sources and quantum nonlinear optics in the "Purcell" regime.

Fabrication of a nanofiber Bragg cavity with high quality factor using a focused helium ion beam

“…Nanofiber cavities, which are optical microcavities embedded in nanofibers, have been developed to further improve the coupling efficiency [22][23][24][25][26]. We have recently developed nanofiber Bragg cavities (NFBCs) using a gallium-ion type focused ion beam (FIB).…”

Optical nanofiber-based cavity induced by periodic air-nanohole arrays

“…25 Keloth et al used this technique to create a centimeter-long cavity on a nanofiber and they proposed that the system could be used for strong-coupling cavity quantum electrodynamics (cQED). 26 A composite photonic crystal cavity based on a nanofiber has also been formed by means of an external grating 27 and has been used to observe a significant enhancement of the spontaneous emission rate of single quantum dots into nanofiber guided modes. 8,9,28 In addition, a fiber ring cavity containing a nanofiber section that strongly couples atoms to the cavity mode has been studied recently.…”

Fabrication of optical nanofibre-based cavities using focussed ion-beam milling: a review

“…F defines the resolution capability of the optical cavity, where F = FSR∕Δ and FSR is the free spectral range. For strong interactions between an atom and a photon, it is required to have C ≫ 1 [50]. However, even for C ≫ 1 there are two coupling regimes that can be used to classify cQED.…”

“…In the literature, there are several different techniques describing how to produce cavities directly in optical nanofibres [42][43][44][47][48][49][50][51]. One method that is proving particularly successful is the use of FIB milling to fabricate Bragg mirrors for fibre-based optical cavities [40,[51][52][53].…”