Superconducting and charge density wave transition in single crystalline LaPt₂Si₂

Area of Science:

• Condensed Matter Physics
• Materials Science

Background:

• Superconductivity (SC) and charge density wave (CDW) phenomena are fundamental in condensed matter physics.
• Understanding the interplay between SC and CDW is crucial for discovering new quantum materials.

Purpose of the Study:

• Investigate the bulk nature of superconductivity (SC) and charge density wave (CDW) transitions in single crystalline LaPt2Si2.
• Explore the competing relationship between CDW and SC phases.
• Characterize the anomalous temperature dependence of the upper critical field (H_C2(T)) and anisotropy in transport and magnetic properties.

Main Methods:

• Single crystal growth of LaPt2Si2.
• Electrical resistivity measurements.
• Heat capacity measurements.
• Magnetic susceptibility measurements.

Main Results:

• Anomalies in electrical resistivity and heat capacity confirm bulk SC and CDW transitions in single crystalline LaPt2Si2.
• The charge density wave transition temperature is lower, while the superconducting transition temperature is higher in single crystals compared to polycrystalline samples, indicating competition.
• An anomalous temperature dependence of the upper critical field (H_C2(T)) was observed.
• Anisotropy in transport and magnetic properties was detected in the single crystal.

Conclusions:

• The study confirms the competing nature of charge density wave and superconductivity in LaPt2Si2 single crystals.
• The findings highlight the importance of crystal structure in mediating the interplay between these quantum phases.
• Further research into the anomalous upper critical field and anisotropy could reveal novel superconducting mechanisms.