Investigating the fast spectral diffusion of a quantum emitter in hBN using resonant excitation and photon correlations

Abstract

The ability to identify and characterize homogeneous and inhomogeneous dephasing processes is crucial in solid-state quantum optics. In particular, spectral diffusion leading to line broadening is difficult to evidence when the associated timescale is shorter than the inverse of the photon detection rate. Here, we show that a combination of resonant laser excitation and second-order photon correlations allows to access such fast dynamics. The resonant laser drive converts spectral diffusion into intensity fluctuations, leaving a signature in the second-order coherence function $g^{(2)}(\tau )$ of the scattered light that can be characterized using two-photon coincidences -- which simultaneously provides the homogeneous dephasing time. We experimentally implement this method to investigate the fast spectral diffusion of a color center generated by an electron beam in the two-dimensional material hexagonal boron nitride. The $g^{(2)}(\tau )$ function of the quantum emitter measured over more than ten orders of magnitude of delay times, at various laser powers, establishes that the color center experiences spectral diffusion at a characteristic timescale of a few tens of microseconds, while emitting Fourier-limited single photons ($T_2/2T_1\sim 1$) between spectral jumps.

References in corpus (6)

• Subnanosecond spectral diffusion measurement using photon correlation
• Ultrafast spectral diffusion measurement on nitrogen vacancy centers in nanodiamonds using correlation interferometry
• Photon-correlation Fourier spectroscopy
• Two-photon interference from a quantum emitter in hexagonal boron nitride
• Cathodoluminescence monitoring of quantum emitter activation in hexagonal boron nitride
• First-order coherence of light emission from inhomogeneously broadened mesoscopic ensembles

Cited by in corpus (7)

• Top-down integration of a hBN quantum emitter in a monolithic photonic waveguide
• Quantum efficiency and vertical position of quantum emitters in hBN determined by Purcell effect in hybrid metal-dielectric planar photonic structures
• Creation and Microscopic Origins of Single-Photon Emitters in Transition Metal Dichalcogenides and Hexagonal Boron Nitride
• Photon statistics of resonantly driven spectrally diffusive quantum emitters
• Reproducible generation of green-emitting color centers in hBN using oxygen annealing
• Time-Resolved Stokes Analysis of Single Photon Emitters in Hexagonal Boron Nitride
• Photon correlation Fourier spectroscopy of a B center in hBN