Synthesis of single-crystalline LuN films

TL;DR

This paper reports the successful epitaxial growth and characterization of single-crystalline LuN films, revealing their semiconducting behavior and magnetic properties, which are crucial for understanding potential room-temperature superconductivity in Lu-H-N systems.

Contribution

The study demonstrates a novel method for synthesizing high-quality single-crystalline LuN films and provides detailed insights into their electronic and magnetic properties.

Findings

LuN films are semiconducting with an activation gap of ~0.02 eV.

Negative magnetoresistance observed below 12 K.

High-resolution X-ray diffraction confirms epitaxial growth.

Abstract

In the nitrogen-doped lutetium hydride (Lu-H-N) system, the presence of Lu-N chemical bonds plays a key role in the emergence of possible room-temperature superconductivity at near ambient pressure. However, due to the synthesis of single-crystalline LuN being a big challenge, the understanding of LuN is insufficient thus far. Here, we report on the epitaxial growth of single-crystalline LuN films. The crystal structures of LuN films were characterized by high-resolution X-ray diffraction. The measurement of low-temperature electrical transport indicates the LuN film is semiconducting from 300 to 2 K, yielding an activation gap of $\sim$ 0.02 eV. Interestingly, negative magnetoresistances can be observed below 12 K, which can result from the defects and magnetic impurities in LuN films. Our results uncover the electronic and magnetic properties of single-crystalline LuN films.