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arXiv · 1611.06763

Phase-channel dynamics reveal the role of impurities and screening in a quasi-one-dimensional charge-density wave system

M. D. Thomson·K. Rabia·F. Meng·M. Bykov·S. van Smaalen·H. G. Roskos
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Abstract

We investigate the low-energy phase excitations of the quasi-one-dimensional charge density wave (CDW) in $\mathrm{K}_{0.3}\mathrm{Mo}\mathrm{O}_3$, by direct probing of infrared-active CDW-lattice modes (phase-phonons) with ultrafast terahertz spectroscopy. Both the nonequilibrium response and temperature dependence of the bands are reconciled by generalizing the time-dependent Ginzburg-Landau theory, beyond that previously applied to the amplitude-phonons, to include impurity effects, while the photoinduced blue-shifts are attributed to a reduction of the electron-phonon coupling induced by a long-lived free-carrier population.

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M. D. Thomson, K. Rabia, F. Meng, M. Bykov, S. van Smaalen, H. G. Roskos. 2016-11-21. Phase-channel dynamics reveal the role of impurities and screening in a quasi-one-dimensional charge-density wave system. https://doi.org/10.1038/s41598-017-02198-x

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