Low Energy Magneto-optics of Tb<sub>2</sub>Ti<sub>2</sub>O<sub>7</sub> in [111] Magnetic Field

ORAL

Abstract

The pyrochlore magnet Tb2Ti2O7 shows a lack of magnetic order to low temperatures and is considered to be a quantum spin liquid candidate. We perform time-domain THz spectroscopy on high quality Tb2Ti2O7 crystal and study the low energy excitations as a function of [111] magnetic field with high energy resolution. The low energy crystal field excitations change their energies anomalously under magnetic field. Despite several sharp field dependent changes, we show that the material’s spectrum can be described not by a phase transitions, but by field dependent hybridization between the low energy crystal field levels. We highlight the strong coupling between spin and lattice degrees of freedom in Tb2Ti2O7 as evidenced by the magnetic field tunable crystal field environment. Calculations based on single ion physics with field induced symmetry reduction of the crystal field environment can reproduce our data.

*This work at JHU was supported as part of the Institute for Quantum Matter, an EFRC funded by the DOE-BES under DESC0019331.

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Presenters

  • Xinshu Zhang

    • Johns Hopkins University

Authors

  • Xinshu Zhang

    • Johns Hopkins University

  • Yi Luo

    • Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University
    • Johns Hopkins University

  • Thomas Halloran

    • Johns Hopkins University

  • Jonathan Gaudet

    • Department of Physics and Astronomy and Institute for Quantum Matter, The Johns Hopkins University
    • Johns Hopkins University
    • Department of Physics and Astronomy and Institute for Quantum Matter, Johns Hopkins University, Baltimore, Maryland 21218, USA

  • Huiyuan Man

    • Geballe Laboratory for Advanced Materials, Stanford University
    • Johns Hopkins University
    • Department of Physics and Astronomy, Johns Hopkins University
    • Stanford University

  • Seyed Koohpayeh

    • Johns Hopkins University

  • Peter Armitage

    • Johns Hopkins University
    • Department of Physics and Astronomy, Johns Hopkins University, Baltimore 21218
    • Department of Physics and Astronomy, Johns Hopkins University