2012/01/17 by S. Haravifard, Sara Haravifard, A. Banerjee +7 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Atomic physics #Condensed matter physics #Diffraction #Ground state #Isotropy #Lattice (music) #Magnet #Magnetic and transport properties of perovskites and related materials #Magnetism #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum mechanics #Quantum phase transition #Reciprocal lattice #Singlet state #cond-mat.other #cond-mat.str-el
paper · pdf · doi:10.1073/pnas.1114464109
published as PNAS v109 p2286-2289 (2012) · 16 pages, 4 figures. Accepted for publication in PNAS
arxiv created 2012/01/17 · openalex publication_date 2012/01/30 · arxiv updated 2012/02/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The Shasty-Sutherland model, which consists of a set of spin 1/2 dimers on a 2D square lattice, is simple and soluble but captures a central theme of condensed matter physics by sitting precariously on the quantum edge between isolated, gapped excitations and collective, ordered ground states. We compress the model Shastry-Sutherland material, SrCu(2)(BO(3))(2), in a diamond anvil cell at cryogenic temperatures to continuously tune the coupling energies and induce changes in state. High-resolution X-ray measurements exploit what emerges as a remarkably strong spin-lattice coupling to both monitor the magnetic behavior and the absence or presence of structural discontinuities. In the low-pressure spin-singlet regime, the onset of magnetism results in an expansion of the lattice with decreasing temperature, which permits a determination of the pressure-dependent energy gap and the almost isotropic spin-lattice coupling energies. The singlet-triplet gap energy is suppressed continuously with increasing pressure, vanishing completely by 2 GPa. This continuous quantum phase transition is followed by a structural distortion at higher pressure.