Lifetime-resolved Photon-Correlation Fourier Spectroscopy

TL;DR

This paper introduces a pulsed laser-based Photon-Correlation Fourier Spectroscopy method that measures spectral diffusion and dynamics of single solid-state emitters with high resolution, discriminating between relaxation and bath fluctuations.

Contribution

It presents a novel lifetime-resolved PCFS technique that captures spectral dynamics along the emission lifetime, useful for complex quantum emitters with multiple states.

Findings

Effective discrimination of spectral diffusion from relaxation processes.

High spectral and temporal resolution in lifetime-resolved measurements.

Applicability to quantum emitters with multiple state contributions.

Abstract

The excited state population of single solid-state emitters is subjected to energy fluctuations around the equilibrium driven by the bath and relaxation through the emission of phonons or photons. Simultaneous measurement of the associated spectral dynamics requires a technique with a high spectral and temporal resolution with an additionally high temporal dynamic range. We propose a pulsed excitation-laser analog of Photon-Correlation Fourier Spectroscopy (PCFS), which extracts the lineshape and spectral diffusion dynamics along the emission lifetime trajectory of the emitter, effectively discriminating spectral dynamics from relaxation and bath fluctuations. This lifetime-resolved PCFS correlates photon-pairs at the output arm of a Michelson interferometer in both their time-delay between laser-excitation and photon-detection and the time-delay between two photons. We propose the utility of the technique for systems with changing relative contributions to the emission from multiple states, for example, quantum emitters exhibiting phonon-mediated exchange between different fine-structure states.