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arXiv · 2512.04029

Anisotropic Phonon Dynamics and Directional Transport in Actinide van der Waals Semiconductor USe$_3$

Aljoscha Söll·Valentino Jadrisko·Sourav Dey·Nassima Benchtaber·Kalyan Sarkar·Borna Radatovic·Jan Luxa·Fedor Lipilin·Kseniia Mosina·Vojtech Kundrat·Jakub Zalesak·Jana Vejpravova·Martin Zacek·Christoph Gadermaier·José J. Baldoví·Zdeněk Sofer
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Abstract

Direction-dependent charge transport and optical responses are characteristic of van der Waals (vdW) materials with strong in-plane anisotropy. While transition-metal trichalcogenides (TMTCs) exemplify this behavior, heavier analogs remain largely unexplored. In this study we examine USe$_3$ as an anisotropic vdW material and a heavier analog of the well-studied TMTCs. We reveal strong in-plane anisotropy using polarization-resolved Raman spectroscopy, investigate strain-induced shifts of phonon modes, and quantify direction-dependent charge-carrier mobility through transport measurements on field-effect devices. First-principles calculations based on density-functional theory corroborate our findings, providing a theoretical basis for our experimental observations. Casting USe$_3$ as an actinide analog of a TMTC establishes a platform for exploring low-dimensional semiconductors that combine strong in-plane anisotropy with f-electron physics.

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Aljoscha Söll, Valentino Jadrisko, Sourav Dey, Nassima Benchtaber, Kalyan Sarkar, Borna Radatovic, Jan Luxa, Fedor Lipilin, Kseniia Mosina, Vojtech Kundrat, Jakub Zalesak, Jana Vejpravova, Martin Zacek, Christoph Gadermaier, José J. Baldoví, Zdeněk Sofer. 2025-12-03. Anisotropic Phonon Dynamics and Directional Transport in Actinide van der Waals Semiconductor USe$_3$. https://arxiv.org/abs/2512.04029

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