Spatial and Spectral Coherent Control with Frequency Combs

TL;DR

This paper demonstrates how counter-propagating broadband pulses combined with optical frequency combs enable precise spatial and spectral control of quantum processes, enhancing applications in spectroscopy, microscopy, and frequency measurement.

Contribution

It introduces a novel spatial control method using broadband pulses with frequency combs, allowing high-resolution spatial and spectral manipulation in quantum systems.

Findings

Generated fully controlled spatial excitation patterns.

Achieved high-precision frequency determination of hyperfine constants.

Reduced decoherence to enhance spectral resolution.

Abstract

Quantum coherent control (1-3) is a powerful tool for steering the outcome of quantum processes towards a desired final state, by accurate manipulation of quantum interference between multiple pathways. Although coherent control techniques have found applications in many fields of science (4-9), the possibilities for spatial and high-resolution frequency control have remained limited. Here, we show that the use of counter-propagating broadband pulses enables the generation of fully controlled spatial excitation patterns. This spatial control approach also provides decoherence reduction, which allows the use of the high frequency resolution of an optical frequency comb (10,11). We exploit the counter-propagating geometry to perform spatially selective excitation of individual species in a multi-component gas mixture, as well as frequency determination of hyperfine constants of atomic rubidium with unprecedented accuracy. The combination of spectral and spatial coherent control adds a new dimension to coherent control with applications in e.g nonlinear spectroscopy, microscopy and high-precision frequency metrology.