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Updated: Jun 3, 2026

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Singlet-triplet excitations in the unconventional spin-Peierls TiOBr compound
J P Clancy1, B D Gaulin, C P Adams
1Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1, Canada.
Abstract:
We have performed time-of-flight neutron scattering measurements on powder samples of the unconventional spin-Peierls compound TiOBr using the fine-resolution Fermi chopper spectrometer (SEQUOIA) at the Spallation Neutron Source at Oak Ridge National Laboratory. These measurements reveal two branches of magnetic excitations within the commensurate and incommensurate spin-Peierls phases, which we associate with n=1 and n=2 triplet excitations out of the singlet ground state. These results represent the first direct measurement of the singlet-triplet energy gap in TiOBr, which has a value of E(g)=21.2±1.0 meV.
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