Localization and interaction effects in strongly underdoped La2-xSrxCuO4

Area of Science:

• Condensed Matter Physics
• Materials Science
• Superconductivity

Background:

• Investigating the electronic properties of La(2-x)Sr(x)CuO4 (LSCO) films is crucial for understanding high-temperature superconductivity.
• The interplay between magnetic ordering and electronic transport in LSCO remains a key area of research.

Purpose of the Study:

• To study the in-plane magnetoresistance (MR) of LSCO films with specific doping levels (0.03 < x < 0.05).
• To elucidate the temperature-dependent evolution of electronic transport mechanisms in LSCO.
• To explore the relationship between magnetic phases and superconducting fluctuations.

Main Methods:

• Measurements of in-plane magnetoresistance (MR) were performed on La(2-x)Sr(x)CuO4 films.
• Experiments were conducted over a temperature range of 1.6 K to 100 K.
• Magnetic fields up to 14 T were applied parallel and perpendicular to the CuO2 planes.

Main Results:

• Magnetoresistance behavior indicates a transition from interaction-dominated effects at high temperatures to spin scattering-dominated effects at low temperatures.
• Weak localization effects were found to be absent in the studied samples.
• A positive orbital magnetoresistance was observed near the antiferromagnetic and spin-glass phase boundary.

Conclusions:

• The findings suggest a gradual shift in dominant scattering mechanisms with decreasing temperature.
• The emergence of orbital MR near magnetic phase boundaries points to complex electronic behavior.
• Evidence for Maki-Thompson superconducting fluctuations was found deep within the insulating phase of LSCO.