Controlled Frustration Release on the Kagome Lattice by Uniaxial-Strain Tuning

• Published in: Physical review letters 2023-12, Vol.131 (25), p.256501-256501, Article 256501
• Main Authors: Wang, Jierong, Spitaler, M, Su, Y-S, Zoch, K M, Krellner, C, Puphal, P, Brown, S E, Pustogow, A
• Format: Article
• Language: English
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.131.256501

It is predicted that strongly interacting spins on a frustrated lattice may lead to a quantum disordered ground state or even form a quantum spin liquid with exotic low-energy excitations. However, a controlled tuning of the frustration strength, separating its effects from those of disorder and other factors, is pending. Here, we perform comprehensive ^{1}H NMR measurements on Y_{3}Cu_{9}(OH)_{19}Cl_{8} single crystals revealing an unusual Q[over →]=(1/3×1/3) antiferromagnetic state below T_{N}=2.2  K. By applying in situ uniaxial stress, we break the symmetry of this disorder-free, frustrated kagome system in a controlled manner yielding a linear increase of T_{N} with strain, in line with theoretical predictions for a distorted kagome lattice. In-plane strain of ≈1% triggers a sizable enhancement ΔT_{N}/T_{N}≈10% due to a release of frustration, demonstrating its pivotal role for magnetic order.