How to measure a spinon Fermi surface

TL;DR

This paper proposes an experimental method to detect a spinon Fermi surface in spin liquids by observing oscillatory coupling between ferromagnets mediated by the spin liquid, with the oscillation period revealing the Fermi wavevector.

Contribution

It introduces a novel experimental approach to identify spinon Fermi surfaces using oscillatory coupling measurements in spin liquid systems.

Findings

Long period oscillations are predicted in all candidate spin liquids.

The oscillation period directly indicates the Fermi wavevector of the spinon surface.

The method provides a practical way to detect spinon Fermi surfaces experimentally.

Abstract

We propose an experiment to identify the potential existence of a spinon Fermi surface by looking for oscillatory coupling between two ferromagnets via a spin liquid spacer. Three candidate spin liquids are investigated, and it is found that in all cases, long period oscillations should be present, the period of which would identify the Fermi wavevector of the spinon surface.