Evidence of Floquet electronic steady states in graphene under continuous-wave mid-infrared irradiation

Yijing Liu; Christopher Yang; Gabriel Gaertner; John Huckabee; Alexey V. Suslov; Gil Refael; Frederik Nathan; Cyprian Lewandowski; Luis E. F. Foa Torres; Iliya Esin; Paola Barbara; Nikolai G. Kalugin

arXiv · 2410.13930

Evidence of Floquet electronic steady states in graphene under continuous-wave mid-infrared irradiation

Yijing Liu·Christopher Yang·Gabriel Gaertner·John Huckabee·Alexey V. Suslov·Gil Refael·Frederik Nathan·Cyprian Lewandowski·Luis E. F. Foa Torres·Iliya Esin·Paola Barbara·Nikolai G. Kalugin

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Abstract

Light-induced phenomena in materials can exhibit exotic behavior that extends beyond equilibrium properties, offering new avenues for understanding and controlling electronic phases. So far, non-equilibrium phenomena in solids have been predominantly explored using femtosecond laser pulses, which generate transient, ultra-fast dynamics. Here, we investigate the steady non-equilibrium regime in graphene induced by a continuous-wave (CW) mid-infrared laser. Our transport measurements reveal signatures of a long-lived Floquet phase, where a non-equilibrium electronic population is stabilized by the interplay between coherent photoexcitation and incoherent phonon cooling. The observation of non-equilibrium steady states using CW lasers opens a new regime for low-temperature Floquet phenomena, paving the way toward Floquet engineering of steady-state phases of matter.

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Yijing Liu, Christopher Yang, Gabriel Gaertner, John Huckabee, Alexey V. Suslov, Gil Refael, Frederik Nathan, Cyprian Lewandowski, Luis E. F. Foa Torres, Iliya Esin, Paola Barbara, Nikolai G. Kalugin. 2024-10-17. Evidence of Floquet electronic steady states in graphene under continuous-wave mid-infrared irradiation. https://arxiv.org/abs/2410.13930

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