Ground-state atomic polarization relaxation-time measurement of Rb filled hypocycloidal core-shaped Kagome HC-PCF

Abstract

We report on the measurement of ground-state atomic polarization relaxation time of Rb vapor confined in five different hypocycloidal core-shape Kagome hollow-core photonic crystal fibers made with uncoated silica glass. We are able to distinguish between wall-collision and transit-time effects in an optical waveguide and deduce the contribution of the atom's dwell time at the core wall surface. In contrast with conventional macroscopic atomic cell configuration, and in agreement with Monte Carlo simulations, the measured relaxation times were found to be at least one order of magnitude longer than the limit set by atom-wall collisional from thermal atoms. This extended relaxation time is explained by the combination of a stronger contribution of the slow atoms in the atomic polarization build-up, and of the relatively significant contribution of dwell time to the relaxation process of the ground state polarization.

Engineering Photon-Photon Interactions within Rubidium-Filled Waveguides

“…To reach such a target, enhancement of the photon-photon interaction strength can be created by performing the photon-atom interaction inside small cross-section and low-loss engineered waveguides. A number of experimental approaches using warm atomic vapors on different platforms have been made using this philosophy including: hollow-core photonic crystal fibers (HC-PCF) [7][8][9][10][11][12][13][14][15][16][17][18], tapered fibers [19][20][21] and exposedcore fibers [22]. These optical fiber approaches have been paralleled by work based on chip-based waveguides [23][24][25][26][27] that aim at better stability and scalability although with higher losses than the fiber approaches.…”