P. Barberis-Blostein

Microscopic models based on multilevel atoms are central to optimizing nonlinear optical responses and the coherent control of light. These models are traditionally based on single-atom effects that are parametrically extrapolated to include collective effects, such as an enhanced response or propagation within atomic media.

Abstract We study a system of two distant quantum emitters coupled via a one-dimensional waveguide where the electromagnetic field has a direction-dependent velocity. As a consequence, the onset of collective emission is nonsimultaneous, and, for appropriate parameters, radiation could be enhanced for one of the emitters while inhibited for the other. Interference effects enable the system to radiate in a preferential direction depending on the atomic state and the field propagation phases.

A tapered single mode ONF, with waist of 240?±?20?nm radius and 7?mm length, is inside an ultrahigh vacuum (UHV) chamber, where it overlaps with a cloud of cold 87Rb atoms (less than half a millimeter width) created from a MOT. The MOT is loaded from a background gas produced by a 87Rb dispenser. Acousto optic modulators (AOMs) control the amplitude and frequencies of the MOT beams. After the atomic cloud loading reaches steady state, the MOT beams are extinguished.