title: Dynamical Stability Limit for the Charge Density Wave in K_{0.3}MoO_{3}.
abstract: We study the response of the one-dimensional charge density wave in K_{0.3}MoO_{3} to different types of excitation with femtosecond optical pulses. We compare direct excitation of the lattice at midinfrared frequencies with injection of quasiparticles across the low energy charge density wave gap and with charge transfer excitation 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 Lindemann criterion for the melting of a crystal lattice.
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany.|University of Hamburg, 22761 Hamburg, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Mankowsky
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Rajasekaran
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany.
authors.forename: H Y
authors.initials: HY
authors.lastname: Liu
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: D
authors.initials: D
authors.lastname: Mou
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: X J
authors.initials: XJ
authors.lastname: Zhou
authors.affiliation: Department of Physics, University of Michigan, Ann Arbor, Michigan 48109-1040, USA.
authors.forename: R
authors.initials: R
authors.lastname: Merlin
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Först
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany.|University of Hamburg, 22761 Hamburg, Germany.|Department of Physics, Oxford University, Clarendon Laboratory, Oxford OX1 3PU, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Cavalleri