Unveiling the multiband metallic nature of the normal state in nickelate La3Ni2O7

TL;DR

This paper investigates the normal state of La3Ni2O7 under high pressure, revealing its multiband metallic nature through transport measurements and magnetoresistance behavior, which is key to understanding its superconductivity.

Contribution

It provides the first systematic study of the pressure-dependent transport properties of La3Ni2O7, highlighting its multiband metallic behavior in the normal state.

Findings

Magnetoresistance shows quasi-quadratic dependence on magnetic field.

Pressure increases metallicity and magnetoresistance, following extended Kohler's rule.

Normal state exhibits multiband metallic characteristics.

Abstract

The discovery of unconventional superconductivity around 80 K in perovskite nickelates under high pressure has furnished a new platform to explore high-temperature unconventional superconductivity in addition to cuprates. Understanding the normal state of nickelate superconductors is crucial to uncovering the origin of this unconventional superconductivity and gaining further insight into its underlying mechanism. In this study, we systemically studied the transport properties of La3Ni2O7 by tuning the pressure under high magnetic fields. Magnetoresistance (MR) consistently exhibits a quasi-quadratic dependence on the magnetic field across all measured pressures and temperatures. Increased pressure enhances the metallicity of the system and leads to a monotonic increase in MR, which follows the extended Kohler's rule. These results suggest that the normal state of La3Ni2O7 to be a multiband metallic nature.