Three-dimensional hidden phase probed by in-plane magnetotransport in kagome metal CsV$_3$Sb$_5$ thin flakes

TL;DR

This study uncovers a new three-dimensional orbital current phase in CsV$_3$Sb$_5$ thin flakes below 35 K, revealed through in-plane magnetotransport measurements, indicating complex interactions among quantum states.

Contribution

It provides magnetotransport evidence of a hidden orbital current phase in kagome metal CsV$_3$Sb$_5$, expanding understanding of its complex phase diagram.

Findings

Identification of a new phase below 35 K with six-fold symmetry in MR

Large negative in-plane magnetoresistance indicating a magnetic field-tunable phase

Connection of the phase to orbital current order in the material

Abstract

Transition metal compounds with kagome structure have been found to exhibit a variety of exotic structural, electronic, and magnetic orders. These orders are competing with energies very close to each other, resulting in complex phase transitions. Some of the phases are easily observable, such as the charge density wave (CDW) and the superconducting phase, while others are more challenging to identify and characterize. Here we present magneto-transport evidence of a new phase below ~35 K in the kagome topological metal CsV$_3$Sb$_5$ (CVS) thin flakes between the CDW and the superconducting transition temperatures. This phase is characterized by six-fold rotational symmetry in the in-plane magnetoresistance (MR) and is connected to the orbital current order in CVS. Furthermore, the phase is characterized by a large in-plane negative magnetoresistance, which suggests the existence of a three-dimensional, magnetic field-tunable orbital current ordered phase. Our results highlight the potential of magneto-transport to reveal the interactions between exotic quantum states of matter and to uncover the symmetry of such hidden phases.