Compact susceptometer for studies under transverse field geometries at very low temperatures

TL;DR

This paper introduces a compact AC susceptometer designed for precise magnetic measurements under transverse field orientations at very low temperatures, suitable for use in cryogenic environments and capable of minimizing parasitic signals.

Contribution

The paper presents a novel, small-sized susceptometer design optimized for transverse magnetic field studies at cryogenic temperatures, with demonstrated application to quantum phase transition measurements.

Findings

Successfully measured transverse susceptibility at quantum critical points.

Achieved minimal parasitic signals and excellent thermal anchoring.

Demonstrated versatility in cryostat and magnet systems.

Abstract

We present the design of a compact AC susceptometer for studies under arbitrarily oriented static magnetic fields, in particular magnetic fields oriented transverse to the AC excitation field. The small size of the susceptometer permits versatile use in conventional cryostats with superconducting magnet systems. The design of the susceptometer minimizes parasitic signal contributions while providing excellent thermal anchoring suitable for measurements in a wide range down to very low temperatures. The performance is illustrated by means of measurements of the transverse susceptibility at the magnetic field tuned quantum phase transition of the dipolar-coupled Ising ferromagnet LiHoF$_4$.