Optically pumped spin polarization as a probe of many-body thermalization

Abstract

The interplay between disorder and transport is a problem central to the understanding of a broad range of physical processes, most notably the ability of a system to reach thermal equilibrium. Disorder and many body interactions are known to compete, with the dominance of one or the other giving rise to fundamentally different dynamical phases. Here we investigate the spin diffusion dynamics of 13C in diamond, which we dynamically polarize at room temperature via optical spin pumping of engineered color centers. We focus on low-abundance, strongly hyperfine-coupled nuclei, whose role in the polarization transport we expose through the integrated impact of variable radio-frequency excitation on the observable bulk 13C magnetic resonance signal. Unexpectedly, we find good thermal contact throughout the nuclear spin bath, virtually independent of the hyperfine coupling strength, which we attribute to effective carbon-carbon interactions mediated by the electronic spin ensemble. In particular, observations across the full range of hyperfine couplings indicate the nuclear spin diffusion constant takes values up to two orders of magnitude greater than that expected from homo-nuclear spin couplings. Our results open intriguing opportunities to study the onset of thermalization in a system by controlling the internal interactions within the bath.

References in corpus (8)

• Many body localization and thermalization in quantum statistical mechanics
• Is efficiency of classical simulations of quantum dynamics related to integrability?
• Tensor network techniques for the computation of dynamical observables in 1D quantum spin systems
• Multi-spin-assisted optical pumping of bulk 13C nuclear spin polarization in diamond
• Quantum parallelism as a tool for ensemble spin dynamics calculations
• Dynamics of frequency-swept nuclear spin optical pumping in powdered diamond at low magnetic fields
• Two-electron-spin ratchets as a platform for microwave-free dynamic nuclear polarization of arbitrary material targets
• Proliferation of effective interactions: decoherence-induced equilibration in a closed many-body system

Cited by in corpus (5)

• Emergent hydrodynamics in a strongly interacting dipolar spin ensemble
• Emergent decoherence induced by quantum chaos in a many-body system: A Loschmidt echo observation through NMR
• The role of electron polarization on nuclear spin diffusion
• Proposal for the search for new spin interactions at the micrometer scale using diamond quantum sensors
• Electron-to-nuclear spectral mapping via "Galton board" dynamic nuclear polarization