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arXiv · 2409.19063

Equilibrium non-linear phononics by electric field fluctuations of terahertz cavities

Emil Viñas Boström·Marios H. Michael·Christian Eckhardt·Angel Rubio
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Abstract

Selective excitation of vibrational modes using strong laser pulses has emerged as a powerful material engineering paradigm. However, to realize deterministic control over material properties for device applications, it is desirable to have an analogous scheme without a drive, operating in thermal equilibrium. We here propose such an equilibrium analog of the light-driven paradigm, leveraging the strong coupling between lattice degrees of freedom and the quantum fluctuations of the electric field of a THz micro-cavity. We demonstrate this approach by showing, using ab initio data, how electric field fluctuations can induce a sub-dominant ferromagnetic order, on top of the dominant zig-zag antiferromagnet order, in FePS$_3$ close to its N\'eel temperature.

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Emil Viñas Boström, Marios H. Michael, Christian Eckhardt, Angel Rubio. 2024-09-27. Equilibrium non-linear phononics by electric field fluctuations of terahertz cavities. https://arxiv.org/abs/2409.19063

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