Unusual Interplay between Superconductivity and Field-Induced Charge Order in YBa_{2}Cu_{3}O_{y}

Area of Science:

• Condensed Matter Physics
• Materials Science
• Superconductivity

Background:

• Understanding the electronic properties of underdoped cuprates is crucial for explaining high-temperature superconductivity.
• The interplay between charge-density waves (CDW) and superconductivity in these materials remains an active area of research.

Purpose of the Study:

• To investigate the temperature and magnetic field dependence of the electronic density of states (DOS) at the Fermi level in underdoped YBa_{2}Cu_{3}O_{y}.
• To explore the relationship between magnetic field-dependent DOS and the onset of charge-density wave order.

Main Methods:

• Specific heat measurements to probe thermodynamic properties.
• Knight shift measurements to determine the electronic spin susceptibility.
• Analysis of the magnetic field dependence of the electronic density of states (DOS).

Main Results:

• The electronic density of states (DOS) at the Fermi level was found to become independent of magnetic field above a characteristic field, H_{DOS}.
• The H_{DOS}(T) line exhibited an unusual inflection near the onset of long-range 3D charge-density wave order.
• The observed 'S' shape of H_{DOS}(T) suggests a cooperative interaction between two distinct electronic orders at low temperatures.

Conclusions:

• The findings indicate a complex interplay of electronic orders in underdoped YBa_{2}Cu_{3}O_{y}.
• The results support the theoretical possibility of a pair-density wave state stabilizing in this system.
• Further theoretical and experimental investigation is warranted to fully understand the phase diagram and the emergent electronic states.