Unusual charge density wave introduced by the Janus structure in monolayer vanadium dichalcogenides

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Symmetry in transition metal dichalcogenides (TMDs) dictates quantum properties, including charge density waves (CDWs).
• Janus structures offer tunable electronic properties, but experimental studies of CDWs in 2D Janus TMDs are scarce due to fabrication challenges.

Purpose of the Study:

• To experimentally fabricate and characterize charge density wave (CDW) states in monolayer Janus VTeSe.
• To elucidate the mechanism behind the observed CDW state in the novel Janus material.

Main Methods:

• Fabrication of monolayer Janus VTeSe via surface selenization of VTe2.
• Experimental characterization using scanning tunneling microscopy (STM).
• Theoretical calculations to understand the electronic and magnetic properties.

Main Results:

• Successful fabrication of monolayer Janus VTeSe.
• Observation and characterization of an unusual [Formula: see text] CDW state breaking threefold rotational symmetry.
• Theoretical confirmation that the CDW arises from magnetic-involved charge modulation, not electron-phonon coupling.

Conclusions:

• Janus VTeSe exhibits a unique magnetic-involved CDW state, distinct from conventional mechanisms.
• This work establishes a new platform for exploring CDW phenomena and tuning electronic properties in 2D TMDs.
• Findings pave the way for fundamental and applied research in advanced electronic materials.