2018/03/15 by Y. Tokiwa, Takuya Yamashita, T. Yamashita +17 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Electron #Ground state #Magnetic monopole #Multiferroics and related materials #Optical conductivity #Phase transition #Photon #Physics #Quantum #Quantum mechanics #Quantum phase transition #Quantum phases #Quantum spin liquid #Quasiparticle #Spin (aerodynamics) #Spin ice #Spin polarization #Spinon #State of matter #Superconductivity #Topological Materials and Phenomena #cond-mat.str-el
paper · pdf · doi:10.7566/jpsj.87.064702
published as J. Phys. Soc. Jpn. 87, 064702 (2018) · 5 pages, 6 figures
arxiv created 2018/03/15 · openalex publication_date 2018/05/07 · arxiv updated 2018/05/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Quantum spin liquid (QSL) is an exotic quantum phase of matter whose ground state is quantum-mechanically entangled without any magnetic ordering. A central issue concerns emergent excitations that characterize QSLs, which are hypothetically associated with quasiparticle fractionalization and topological order. Here we report highly unusual heat conduction generated by the spin degrees of freedom in a QSL state of the pyrochlore magnet Pr2Zr2O7, which hosts spin-ice correlations with strong quantum fluctuations. The thermal conductivity in high temperature regime exhibits a two-gap behavior, which is consistent with the gapped excitations of magnetic (M-) and electric monopoles (E-particles). At very low temperatures below 200 mK, the thermal conductivity unexpectedly shows a dramatic enhancement, which well exceeds purely phononic conductivity, demonstrating the presence of highly mobile spin excitations. This new type of excitations can be attributed to emergent photons (ν-particle), coherent gapless spin excitations in a spin-ice manifold.