Optically Probing Unconventional Superconductivity in Atomically Thin Bi₂Sr₂Ca_0.92Y_0.08Cu₂O_8+δ

Area of Science:

• Condensed Matter Physics
• Materials Science
• Superconductivity

Background:

• Atomically thin cuprates offer unique superconducting properties but face fabrication challenges.
• Understanding their behavior is crucial for novel applications.
• Previous studies were limited by fabrication difficulties.

Purpose of the Study:

• To noninvasively study unconventional superconductivity in atomically thin Y-Bi2212.
• To investigate the influence of the environment on superconductivity in monolayer cuprates.
• To provide optical evidence for the intralayer nature of the superconducting condensate.

Main Methods:

• Utilized an optical pump-probe spectroscopy technique.
• Studied atomically thin Bi2Sr2Ca0.92Y0.08Cu2O8+δ (Y-Bi2212) flakes.
• Exploited the spatial resolution of the optical probe.

Main Results:

• Observed an optical response similar to bulk Y-Bi2212 during the superconducting phase transition.
• Found significant variations in pump-probe signal based on dielectric environment and excitation.
• Demonstrated exceptional environmental sensitivity of monolayer Y-Bi2212.

Conclusions:

• Provided the first optical evidence for the intralayer nature of superconductivity in Bi2212.
• Highlighted the critical role of double-sided encapsulation in maintaining superconductivity.
• Underscored the environmental sensitivity of atomically thin cuprates.