English

Energy Exchange between Phononic and Electronic Subsystem Governing The Nonlinear Conduction in DCNQI$_2$Cu

Strongly Correlated Electrons 2015-10-09 v2 Materials Science

Abstract

We present a dynamical study on the nonlinear conduction behaviour in the commensurate charge-density-wave phase of the quasi-one-dimensional conductor DCNQI2_2Cu below 75 K. We can accurately simulate magnitude and time-dependence of the measured conductivity in response to large voltage pulses by accounting for the energy exchange between the phononic and electronic subsystems by means of an electrothermal model. Our simulations reveal a distinct non-equilibrium population of optical phonon states with an average energy of Eph_{ph} = 19 meV being half the activation energy of about Δ\DeltaEa_a = 39 meV observed in DC resistivity measurements. By inelastic scattering, this hot optical phonon bath generates additional charge-carrying excitations thus providing a multiplication effect while energy transferred to the acoustic phonons is dissipated out of the system via heat conduction. Therefore, in high electric fields a preferred interaction of charge-carrying excitations with optical phonons compared to acoustic phonon modes is considered to be responsible for the nonlinear conduction effects observed in DCNQI2_2Cu.

Keywords

Cite

@article{arxiv.1505.04907,
  title  = {Energy Exchange between Phononic and Electronic Subsystem Governing The Nonlinear Conduction in DCNQI$_2$Cu},
  author = {Florian Huewe and Alexander Steeger and Irene Bauer and Steffen Doerrich and Peter Strohriegl and Jens Pflaum},
  journal= {arXiv preprint arXiv:1505.04907},
  year   = {2015}
}