Long-Range Photon Fluctuations Enhance Photon-Mediated Electron Pairing and Superconductivity

Area of Science:

• Condensed Matter Physics
• Quantum Optics
• Materials Science

Background:

• Superconductivity in two-dimensional (2D) materials is a key area of research.
• Conventional Bardeen-Cooper-Schrieffer (BCS) theory explains phonon-mediated superconductivity.
• Cavity-mediated interactions offer a novel route to induce superconductivity.

Purpose of the Study:

• To investigate cavity-mediated pairing as a mechanism for inducing superconductivity in 2D materials.
• To analyze the role of photon fluctuations and nonadiabatic photons in pairing.
• To explore factors influencing the superconducting critical temperature (Tc).

Main Methods:

• Theoretical analysis of cavity-mediated electron-electron interactions.
• Modeling of pairing processes involving adiabatic and nonadiabatic photons.
• Investigation of the dependence of Tc on coupling strength, photon fluctuations, and electron properties.
• Inclusion of cavity loss and finite photon numbers in the model.

Main Results:

• Cavity-mediated interactions lead to long-range electron pairing.
• Photon fluctuations significantly enhance pairing, enabling non-BCS-type processes.
• The critical temperature depends on electron dispersion and lifetime at the Fermi surface, not just occupation.
• Realistic parameters, including cavity loss, predict Tc over an order of magnitude higher than BCS theory.
• Finite photon numbers further increase Tc.

Conclusions:

• Cavity-mediated pairing is a promising mechanism for achieving high-temperature superconductivity in 2D materials.
• Photon fluctuations and electron lifetime are crucial for enhancing Tc in this regime.
• This approach offers a pathway to engineer superconducting properties beyond conventional BCS limitations.