Magnetostriction studies up to megagauss fields using fiber Bragg grating technique

TL;DR

This paper introduces a high-speed fiber Bragg grating technique for measuring magnetostriction under pulsed megagauss magnetic fields, demonstrating its effectiveness on various magnetic materials.

Contribution

The study develops and validates a 100 MHz fiber Bragg grating-based method for magnetostriction measurements in ultra-high magnetic fields, enabling rapid and reliable data collection.

Findings

Successful magnetostriction measurements up to megagauss fields.

Validation of the method on solid oxygen, volborthite, CaV4O9, and LaCoO3.

Demonstrated high-speed measurement capability in pulsed magnetic environments.

Abstract

We here report magnetostriction measurements under pulsed megagauss fields using a high-speed 100 MHz strain monitoring system devised using fiber Bragg grating (FBG) technique with optical filter method. The optical filter method is a detection scheme of the strain of FBG, where the changing Bragg wavelength of the FBG reflection is converted to the intensity of reflected light to enable the 100 MHz measurement. In order to show the usefulness and reliability of the method, we report the measurements for solid oxygen, spin-controlled crystal, and volborthite, a deformed Kagom\'{e} quantum spin lattice, using static magnetic fields up to 7 T and non-destructive millisecond pulse magnets up to 50 T. Then, we show the application of the method for the magnetostriction measurements of CaV$_{4}$O$_{9}$, a two-dimensional antiferromagnet with spin-halves, and LaCoO$_{3}$, an anomalous spin-crossover oxide, in the megagauss fields.