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arXiv · 1702.05897

A dynamical stability limit for the charge density wave in K0.3MoO3

Roman Mankowsky·Biaolong Liu·Srivats Rajasekaran·Haiyun Liu·Daixiang Mou·X. J. Zhou·Roberto Merlin·Michael Först·Andrea Cavalleri
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Abstract

We study the response of the one-dimensional charge density wave in K0.3MoO3 to different types of excitation with femtosecond optical pulses. We compare the response to direct excitation of the lattice at mid-infrared frequencies with that to the injection of quasi-particles across the low-energy charge density wave gap and to charge transfer excitations in the near infrared. For all three cases, we observe a fluence threshold above which the amplitude-mode oscillation frequency is softened and the mode becomes increasingly damped. We show that all the data can be collapsed onto a universal curve in which the melting of the charge density wave occurs abruptly at a critical lattice excursion. These data highlight the existence of a universal stability limit for a charge density wave, reminiscent of the empirical Lindemann criterion for the stability of a crystal lattice.

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Roman Mankowsky, Biaolong Liu, Srivats Rajasekaran, Haiyun Liu, Daixiang Mou, X. J. Zhou, Roberto Merlin, Michael Först, Andrea Cavalleri. 2017-02-20. A dynamical stability limit for the charge density wave in K0.3MoO3. https://doi.org/10.1103/physrevlett.118.116402

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