Lattice-decoupled rotatable stripe-like charge order within the strange metal phase of 2M-WS2

TL;DR

This study uncovers a unique rotatable stripe-like charge order in 2M-WS2 that coexists with superconductivity, challenging traditional understanding of charge order orientation and suggesting a link to the strange metal phase.

Contribution

It reveals a lattice-decoupled, rotatable charge order with multiple orientations in 2M-WS2, not explained by phonon spectra or nesting, indicating novel mechanisms involving electronic correlations.

Findings

Charge order has five distinct orientations with identical wavelength.

Transition temperature varies spatially from 21 to 46 K.

Charge order correlates with the strange metal phase.

Abstract

In quantum materials, charge orders typically stabilize in specific crystallographic orientations, though their formation mechanisms may vary. Here, using low-temperature scanning tunneling microscopy (STM), we discover a lattice-decoupled rotatable stripe-like charge order coexisting with superconductivity in 2M-WS2. The charge order manifests five distinct orientations across different sample regions, yet maintains an identical wavelength. This directional decoupling from host lattice challenges existing paradigms. First-principles calculations of phonon spectra and nesting function fail to explain the ordering mechanism. Intriguingly, the transition temperature of the charge orders exhibits spatial variations (21-46 K), coinciding with the temperature range of the recently reported strange metal phase in this material. This correlation suggests that the interplay between strong electronic correlations and electron-phonon coupling must be critically evaluated to elucidate the emergence of this unconventional charge order.