Superconductivity Reinforces Charge-Density-Wave Phase Coherence across Cuprates

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Materials

Background:

• High-temperature cuprates exhibit complex electronic phases, including superconductivity and charge-density-wave (CDW) order.
• The interplay between superconductivity and CDW order in cuprates has been traditionally viewed as antagonistic, with superconductivity suppressing CDW properties.

Purpose of the Study:

• To investigate the detailed relationship between superconductivity and charge-density-wave (CDW) order in high-T_{c} cuprates.
• To challenge the established view of superconductivity solely suppressing CDW order.

Main Methods:

• Utilized resonant soft x-ray scattering (RSXS) for probing electronic order.
• Employed a coherence-sensitive momentum-profile analysis to quantify CDW phase coherence.
• Examined multiple cuprate families, including Bi-, Hg-, Y-, and Nd-based compounds.

Main Results:

• Discovered a systematic enhancement of CDW phase coherence below the superconducting critical temperature (T_{c}).
• Observed a BCS-like growth of phase coherence, evidenced by the absence of CDW peak broadening and near-perfect wave-vector locking.
• Demonstrated that this enhancement persists even in aged, disordered samples and is consistent across different cuprate families.

Conclusions:

• Superconductivity in high-T_{c} cuprates plays a dual role: suppressing CDW amplitude while strengthening its phase coherence.
• Revealed a significant phase-level interplay between superconductivity and lattice coupling in these materials.
• The findings necessitate a revised understanding of the competition and coexistence of electronic orders in cuprates.