Strain as a tool to stabilize the isotropic triangular lattice in a geometrically frustrated organic quantum magnet

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Lieberich, Francisco, Saito, Yohei, Agarmani, Yassine, Sasaki, Takahiko, Yoneyama, Naoki, Winter, Stephen M., Lang, Michael, Gati, Elena
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916838180388864
author Lieberich, Francisco
Saito, Yohei
Agarmani, Yassine
Sasaki, Takahiko
Yoneyama, Naoki
Winter, Stephen M.
Lang, Michael
Gati, Elena
author_facet Lieberich, Francisco
Saito, Yohei
Agarmani, Yassine
Sasaki, Takahiko
Yoneyama, Naoki
Winter, Stephen M.
Lang, Michael
Gati, Elena
contents Geometric frustration is a key ingredient in the emergence of exotic states of matter, such as the quantum spin liquid in Mott insulators. While there has been intense interest in experimentally tuning frustration in candidate materials, achieving precise and continuous control has remained a major hurdle -- particularly in accessing the properties of the ideally frustrated lattice. Here, we show that large, finely controlled anisotropic strains can effectively tune the degree of geometric frustration in the Mott insulating $κ$-(ET)$_2$Cu$_2$(CN)$_3$ -- a slightly anisotropic triangular-lattice quantum magnet. Using thermodynamic measurements of the elastocaloric effect, we experimentally map out a temperature-strain phase diagram that captures both the ground state of the isotropic lattice and the less frustrated parent state. Our results provide a new benchmark for calculations of the triangular-lattice Hubbard model as a function of frustration and highlight the power of lattice engineering as a route to realizing perfectly frustrated quantum materials.
format Preprint
id arxiv_https___arxiv_org_abs_2506_23813
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Strain as a tool to stabilize the isotropic triangular lattice in a geometrically frustrated organic quantum magnet
Lieberich, Francisco
Saito, Yohei
Agarmani, Yassine
Sasaki, Takahiko
Yoneyama, Naoki
Winter, Stephen M.
Lang, Michael
Gati, Elena
Strongly Correlated Electrons
Geometric frustration is a key ingredient in the emergence of exotic states of matter, such as the quantum spin liquid in Mott insulators. While there has been intense interest in experimentally tuning frustration in candidate materials, achieving precise and continuous control has remained a major hurdle -- particularly in accessing the properties of the ideally frustrated lattice. Here, we show that large, finely controlled anisotropic strains can effectively tune the degree of geometric frustration in the Mott insulating $κ$-(ET)$_2$Cu$_2$(CN)$_3$ -- a slightly anisotropic triangular-lattice quantum magnet. Using thermodynamic measurements of the elastocaloric effect, we experimentally map out a temperature-strain phase diagram that captures both the ground state of the isotropic lattice and the less frustrated parent state. Our results provide a new benchmark for calculations of the triangular-lattice Hubbard model as a function of frustration and highlight the power of lattice engineering as a route to realizing perfectly frustrated quantum materials.
title Strain as a tool to stabilize the isotropic triangular lattice in a geometrically frustrated organic quantum magnet
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2506.23813