Superconductivity in an extreme strange metal

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Materials

Background:

• High-transition-temperature superconductors often exhibit linear-in-temperature 'strange metal' or 'Planckian' electrical resistivity.
• This behavior is widely considered crucial for understanding high-temperature superconductivity.
• Complex phase diagrams in these materials obscure the underlying physics.

Purpose of the Study:

• To investigate the nature of the strange metal state in high-transition-temperature superconductors.
• To identify the mechanism driving superconductivity in these materials.
• To explore the relationship between strange metallic behavior and superconductivity.

Main Methods:

• Electrical resistivity measurements were conducted down to the micro-Kelvin temperature regime.
• Analysis focused on the temperature dependence of resistivity over an extended range.
• Investigated the transition from a strange metal state to a superconducting state.

Main Results:

• Superconductivity was observed to condense out of an extreme strange metal state.
• The strange metal state exhibited linear resistivity across 3.5 orders of magnitude in temperature.
• Evidence suggests Cooper pairing is mediated by dynamical charge localization-delocalization transition modes.

Conclusions:

• The study reveals a novel pathway to superconductivity originating from an extreme strange metal.
• A proposed mechanism involving charge localization-delocalization may be relevant for other strange metal superconductors.
• This work advances the understanding of exotic electronic states and their role in superconductivity.