Johnathan Kowalski | Searcharxiv

arXiv2026

Dual Charge-Density-Waves in Two-dimensional DyTe3 and Their Distinct Impacts on Magneto-Transport Properties

Charge-density-waves (CDWs) are macroscopic quantum states defined by periodic modulations in electronic charge density coupled with lattice distortions. Despite significant research efforts, the evolution of electromagnetic transport properties in the presence of CDWs remains largely unexplored. Here, we report the effects of two orthogonal CDWs (CDW1 and CDW2) coexisting at low-temperature in DyTe3 on its electronic transport properties. Importantly, we find that while no clear magnetotransport anomaly is resolved across CDW1 transition under the present experimental conditions, the emergence of CDW2 drives a drastic enhancement in magnetoresistance and a multiband-governed nonlinear Hall response. These results demonstrate that CDW1 and CDW2 in DyTe3 are fundamentally different and impact its electronic transport in qualitatively distinct ways, establishing DyTe3 as a model system for understanding the transport consequences of multiple CDWs in quasi-two-dimensional materials.

cond-mat.str-el↗

arXiv2025

Raman Digital Twin of Monolayer Janus Transition Metal Dichalcogenides

Monolayer transition metal dichalcogenides (TMDs) are a key class of two-dimensional (2D) materials with broad technological potential. Their Janus counterparts exhibit unique properties due to broken out-of-plane symmetry and further enrich the functionalities of TMDs. However, experimental synthesis and identification of Janus TMDs remain challenging. It is thus highly desirable to have a rapid, simple, and in situ characterization technique to monitor, in real time, the conversion process from the parent to Janus structure. Raman spectroscopy stands out for such a task as it is a powerful, non-destructive, and very commonly used tool to characterize 2D materials both in situ and ex situ. To realize the full potential of Raman spectroscopy on rapid characterization of Janus TMDs, we present a computational "Raman digital twin" library for various monolayer Janus TMDs in both 2H and Td phases. We focus on group-6 TMDs: MoS$_2$, WS$_2$, MoSe$_2$, WSe$_2$, MoTe$_2$, WTe$_2$ and their Janus variants: MoSSe, MoSTe, MoSeTe, WSSe, WSTe, and WSeTe. Using first-principles density functional theory (DFT), we calculate their vibrational properties and predict distinct Raman fingerprints. These phonon and Raman signatures reflect each material's structural symmetry and atomic composition, enabling clear identification via Raman spectroscopy. Our theoretical work supports experimental efforts by providing benchmarks for material identification, structural analysis, and quality control. The computational library expedites the discovery and development of Janus 2D materials, facilitating tighter integration between theoretical predictions and experimental validation.

cond-mat.mtrl-sci↗