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arXiv · 2608.23230

Revealing Hidden Orbital Pathways in NonThermal Hot Carrier Relaxation of MXenes via Non-Secular Redfield Quantum Kinetic

Ali Asghar Molavi Choobini·Abbas Chimeh·Jinhui Zhong
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Abstract

Nonthermal carrier relaxation is routinely inferred from population dynamics or spectroscopic observables, yet neither class of quantity uniquely identifies the microscopic channels through which energy and coherence are redistributed. We introduce a pathway-resolved quantum kinetic framework that simultaneously projects ultrafast relaxation onto orbital populations, inter-orbital energy fluxes, coherence, spectroscopic visibility, and a hidden-pathway sector of the dynamical transfer network. Application to MXenes exposes strongly nonuniform orbital redistribution together with material specific hierarchies of microscopic transfer channels. Temperature, excitation amplitude, and dissipative parameters modulate pathway competition and spectral amplitudes while leaving the identity of the dominant channels largely intact. Instantaneous energy flux, cumulative transfer, coherence, and spectroscopic visibility are shown to follow inequivalent hierarchical orderings. This nonequivalence isolates a set of hidden pathways that remain dynamically consequential despite weak conventional spectroscopic signatures. The resulting time energy coherence representation recasts nonthermal relaxation as a structured dynamical network comprising observable and hidden sectors, thereby providing a general methodology for resolving microscopic energy-transfer pathways in driven quantum materials.

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Ali Asghar Molavi Choobini, Abbas Chimeh, Jinhui Zhong. 2026-08-24. Revealing Hidden Orbital Pathways in NonThermal Hot Carrier Relaxation of MXenes via Non-Secular Redfield Quantum Kinetic. https://arxiv.org/abs/2608.23230

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