Quantum phases of SrCu₂(BO₃)₂ from high-pressure thermodynamics
Files
Accepted manuscript
Date
2020-05-22
Authors
Guo, Jing
Sun, Guangyu
Zhao, Bowen
Wang, Ling
Hong, Wenshan
Sidorov, Vladimir A.
Ma, Nvsen
Wu, Qi
Li, Shiliang
Meng, Zi Yang
Version
Accepted manuscript
OA Version
Citation
Jing Guo, Guangyu Sun, Bowen Zhao, Ling Wang, Wenshan Hong, Vladimir A Sidorov, Nvsen Ma, Qi Wu, Shiliang Li, Zi Yang Meng, Anders W Sandvik, Liling Sun. 2020. "Quantum Phases of SrCu_{2}(BO_{3})_{2} from High-Pressure Thermodynamics.." Phys Rev Lett, Volume 124, Issue 20, pp. 206602 - ?. https://doi.org/10.1103/PhysRevLett.124.206602
Abstract
We report heat capacity measurements of SrCu₂(BO₃)₂ under high pressure along with simulations of relevant quantum spin models and map out the (P,T) phase diagram of the material. We find a first-order quantum phase transition between the low-pressure quantum dimer paramagnet and a phase with signatures of a plaquette-singlet state below T=2 K. At higher pressures, we observe a transition into a previously unknown antiferromagnetic state below 4 K. Our findings can be explained within the two-dimensional Shastry-Sutherland quantum spin model supplemented by weak interlayer couplings. The possibility to tune SrCu₂(BO₃)₂ between the plaquette-singlet and antiferromagnetic states opens opportunities for experimental tests of quantum field theories and lattice models involving fractionalized excitations, emergent symmetries, and gauge fluctuations.