Imaging Sublattice Cooper-Pair Density Waves in Monolayer 1  T^{'}-MoTe_{2}

Area of Science:

• Condensed Matter Physics
• Materials Science
• Superconductivity

Background:

• Unconventional superconductors exhibit spatial modulations of their superconducting order parameter.
• Symmetry breaking in strongly correlated materials leads to pair density waves.

Purpose of the Study:

• To investigate sublattice modulations of superconducting properties in tunable 1T'-MoTe2 monolayer.
• To understand the interplay between pair density waves and unconventional superconductivity.

Main Methods:

• Spectroscopic-imaging scanning tunneling microscopy was employed.
• Analysis of superconducting gap magnitude, coherence strength, and subgap states.

Main Results:

• Sublattice modulations of superconducting properties were observed, oriented perpendicular to Mo chains.
• Coexistence of half-unit-cell and three-unit-cell pair density wave modulations.
• Modulations were found to attenuate with increasing temperature and magnetic fields.

Conclusions:

• The observed modulations are linked to unconventional electron pairing mechanisms.
• These findings deviate from conventional Bardeen-Cooper-Schrieffer superconductivity.
• The study advances knowledge of pair density modulations in strongly correlated superconductors.