High-Temperature Superconductivity in Boron-Doped Q-Carbon

Area of Science:

• Materials Science
• Condensed Matter Physics
• Superconductivity

Background:

• Superconductivity is a quantum mechanical phenomenon where a material can conduct electricity with zero resistance.
• Achieving high-temperature superconductivity remains a significant challenge in materials science.
• Boron-doped diamond has shown superconductivity, but with limited transition temperatures.

Purpose of the Study:

• To investigate the potential for high-temperature superconductivity in non-equilibrium synthesized carbon materials.
• To explore the effects of boron doping and rapid quenching on carbon's electronic properties.
• To develop novel synthesis methods for advanced superconducting materials.

Main Methods:

• Synthesis of boron-doped amorphous carbon films.
• Nanosecond laser melting and rapid quenching to form a super-undercooled state.
• Magnetic susceptibility measurements to detect superconductivity.

Main Results:

• High-temperature superconductivity observed in B-doped Q-carbon.
• Superconducting transition temperature (T_c) of 36.0 ± 0.5 K achieved at 17.0 ± 1.0 atom % boron.
• T_c is significantly higher than previously reported values for B-doped diamond (11 K).

Conclusions:

• Non-equilibrium synthesis via undercooling can yield materials with enhanced superconducting properties.
• B-doped Q-carbon represents a new class of high-temperature superconductors.
• The observed superconductivity is attributed to strong electron-phonon coupling in the dense, metallic carbon liquid state.