Superatomic-Charge-Density-Wave in Cluster-Assembled Au₆Te₁₂Se₈ Superconductors

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Superatomic crystals are hierarchical materials built from atomically precise clusters.
• Au6Te12Se8 is an all-inorganic superatomic superconductor exhibiting superatomic-charge-density-wave (S-CDW).

Purpose of the Study:

• Investigate the response of S-CDW and superconductivity to external pressure in superatomic crystals.
• Understand the pressure-induced phase transitions and conductivity changes in Au6Te12Se8.

Main Methods:

• In situ synchrotron X-ray diffraction.
• Theoretical calculations.
• Transport measurements under varying pressure.

Main Results:

• S-CDW exhibits a low pressure threshold (0.1 GPa) for response to external pressure.
• A second superconducting phase emerges above 7.3 GPa, increasing the transition temperature (Tc) to 8.5 K.
• Pressure induces superatom slip and a Fermi surface topological transition, causing a conductivity dimensional crossover.

Conclusions:

• Au6Te12Se8 demonstrates a unique pressure-dependent interplay between S-CDW and superconductivity.
• The observed re-entrant superconductivity is linked to a dimensional crossover in conductivity and Fermi surface topology.
• Superatomic crystals offer a novel platform for exploring quantum phenomena under pressure.