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arXiv · 1603.01164

Measurement of collective excitations in VO$_2$ by resonant inelastic X-ray scattering

Haowei He·A. X. Gray·P. Granitzka·J. W. Jeong·N. P. Aetukuri·R. Kukreja·Lin Miao·Y. B. Huang·P. Olalde-Velasco·J. Pelliciari·W. F. Schlotter·E. Arenholz·T. Schmitt·M. G. Samant·S. S. P. Parkin·H. A. Dürr·L. Andrew Wray
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Abstract

Vanadium dioxide is of broad interest as a spin-1/2 electron system that realizes a metal-insulator transition near room temperature, due to a combination of strongly correlated and itinerant electron physics. Here, resonant inelastic X-ray scattering is used to measure the excitation spectrum of charge, spin, and lattice degrees of freedom at the vanadium L-edge under different polarization and temperature conditions. These spectra reveal the evolution of energetics across the metal-insulator transition, including the low temperature appearance of a strong candidate for the singlet-triplet excitation of a vanadium dimer.

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Haowei He, A. X. Gray, P. Granitzka, J. W. Jeong, N. P. Aetukuri, R. Kukreja, Lin Miao, Y. B. Huang, P. Olalde-Velasco, J. Pelliciari, W. F. Schlotter, E. Arenholz, T. Schmitt, M. G. Samant, S. S. P. Parkin, H. A. Dürr, L. Andrew Wray. 2016-03-03. Measurement of collective excitations in VO$_2$ by resonant inelastic X-ray scattering. https://doi.org/10.1103/physrevb.94.161119

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