# Magnetic Transitions under Ultrahigh Magnetic Fields of up to 130 T in   the Breathing Pyrochlore Antiferromagnet LiInCr4O8

**Authors:** Yoshihiko Okamoto, Daisuke Nakamura, Atsushi Miyake, Shojiro Takeyama,, Masashi Tokunaga, Akira Matsuo, Koichi Kindo, and Zenji Hiroi

arXiv: 1704.02784 · 2020-06-12

## TL;DR

This study investigates the magnetic behavior of the breathing pyrochlore antiferromagnet LiInCr4O8 under ultrahigh magnetic fields up to 130 T, revealing a half magnetization plateau and evidence of a spin gap, highlighting strong spin-lattice coupling.

## Contribution

It provides the first detailed high-field magnetization data for breathing pyrochlore antiferromagnets, demonstrating unique frustrated magnetic states with strong spin-lattice interactions.

## Key findings

- Observation of a half magnetization plateau above 90 T
- Identification of a 2.2 meV spin gap in LiGa0.125In0.875Cr4O8
- Strong spin-lattice coupling in the breathing pyrochlore system

## Abstract

The magnetization processes of the spin-3/2 antiferromagnet LiInCr4O8 comprising a "breathing" pyrochlore lattice, which is an alternating array of small and large tetrahedra, are studied under ultrahigh magnetic fields of up to 130 T using state-of-the-art pulsed magnets. A half magnetization plateau is observed above 90 T to 130 T, suggesting that LiInCr4O8 has a strong spin-lattice coupling, similar to conventional chromium spinel oxides. The magnetization of LiGa0.125In0.875Cr4O8, in which the structural and magnetic transitions at low temperatures have been completely suppressed, shows a sudden increase above 13 T, indicating that a spin gap of 2.2 meV exists between a tetramer singlet ground state and an excited state with total spin 1, with the latter being stabilized by the application of a magnetic field. The breathing pyrochlore antiferromagnet is found to be a unique frustrated system with strong spin-lattice coupling and bond alternation.

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Source: https://tomesphere.com/paper/1704.02784