Nesting properties and anisotropy of the Fermi surface of LuNi$_{2}$B$_{2}$C

TL;DR

This paper reports the first direct measurement of the Fermi surface of LuNi₂B₂C, revealing nesting features that explain magnetic phenomena and coexistence of antiferromagnetism and superconductivity in this compound.

Contribution

The study provides the first direct experimental observation of a specific Fermi surface sheet in LuNi₂B₂C, linking its nesting properties to magnetic and superconducting behaviors.

Findings

Identified nesting features on the Fermi surface.

Observed a specific Fermi surface sheet responsible for magnetic structures.

Linked Fermi surface nesting to coexistence of magnetism and superconductivity.

Abstract

The rare earth nickel borocarbides, with the generic formula $R$Ni$_{2}$B$_{2}$C, have recently been shown to display a rich variety of phenomena. Most striking has been the competition between, and even coexistence of, antiferromagnetism and superconductivity. We have measured the Fermi surface (FS) of LuNi$_{2}$B$_{2}$C, and shown that it possesses nesting features capable of explaining some of the phenomena experimentally observed. In particular, it had previously been conjectured that a particular sheet of FS is responsible for the modulated magnetic structures manifest in some of the series. We report the first direct experimental observation of this sheet.