Mechanical sensing of metamagnetic tricriticality in two-dimensional CrI3

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Liu, Feng, Xiao, Jiayong, Jiang, Shengwei, Mak, Kin Fai, Shan, Jie
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911404302270464
author Liu, Feng
Xiao, Jiayong
Jiang, Shengwei
Mak, Kin Fai
Shan, Jie
author_facet Liu, Feng
Xiao, Jiayong
Jiang, Shengwei
Mak, Kin Fai
Shan, Jie
contents Layered Ising metamagnets are antiferromagnetic (AF) materials consisting of monolayer Ising ferromagnets coupled to each other via interlayer AF interactions. They exhibit rich magnetic phase diagrams, featuring tricritical and critical end points, due to the competing magnetic interactions and the Ising anisotropy. While conventional thermodynamic probes can identify these critical points in bulk Ising metamagnets, achieving this in the two-dimensional (2D) limit, where enhanced fluctuation effects can substantially modify critical phenomena, remains to be realized. Here, we combine specific heat capacity (C_V) and magnetic circular dichroism measurements to identify these critical points, extract a tricritical exponent, and map out the complete magnetic phase diagram of 2D Ising metamagnetic CrI3. This is achieved in a nanomechanical device of 6-layer CrI3, in which a direct measurement of the temperature derivative of its mechanical resonance frequency gives C_V. The tricritical point is identified by the onset of an abrupt spin-flip transition on one side and, on the other side, by a vanishing specific heat λ-anomaly for a continuous AF phase transition. In contrast, only the spin-flip transition remains near the critical end point. Our results establish nanomechanical calorimetry as a general route to classify metamagnetic phase transitions and to study multicritical phenomena in 2D magnets.
format Preprint
id arxiv_https___arxiv_org_abs_2601_20398
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Mechanical sensing of metamagnetic tricriticality in two-dimensional CrI3
Liu, Feng
Xiao, Jiayong
Jiang, Shengwei
Mak, Kin Fai
Shan, Jie
Mesoscale and Nanoscale Physics
Layered Ising metamagnets are antiferromagnetic (AF) materials consisting of monolayer Ising ferromagnets coupled to each other via interlayer AF interactions. They exhibit rich magnetic phase diagrams, featuring tricritical and critical end points, due to the competing magnetic interactions and the Ising anisotropy. While conventional thermodynamic probes can identify these critical points in bulk Ising metamagnets, achieving this in the two-dimensional (2D) limit, where enhanced fluctuation effects can substantially modify critical phenomena, remains to be realized. Here, we combine specific heat capacity (C_V) and magnetic circular dichroism measurements to identify these critical points, extract a tricritical exponent, and map out the complete magnetic phase diagram of 2D Ising metamagnetic CrI3. This is achieved in a nanomechanical device of 6-layer CrI3, in which a direct measurement of the temperature derivative of its mechanical resonance frequency gives C_V. The tricritical point is identified by the onset of an abrupt spin-flip transition on one side and, on the other side, by a vanishing specific heat λ-anomaly for a continuous AF phase transition. In contrast, only the spin-flip transition remains near the critical end point. Our results establish nanomechanical calorimetry as a general route to classify metamagnetic phase transitions and to study multicritical phenomena in 2D magnets.
title Mechanical sensing of metamagnetic tricriticality in two-dimensional CrI3
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2601.20398