• DOI:10.1038/s41467-020-16133-8
• Corpus ID: 207870209

Non-perturbative terahertz high-harmonic generation in the three-dimensional Dirac semimetal Cd3As2

@article{Kovalev2019NonperturbativeTH,
  title={Non-perturbative terahertz high-harmonic generation in the three-dimensional Dirac semimetal Cd3As2},
  author={Sergey Kovalev and Renato M. A. Dantas and Semyon Germanskiy and Jan-Christoph Deinert and Bertram Green and Igor E. Ilyakov and Nilesh Awari and Min Chen and Mohammed Bawatna and Jiwei Ling and Faxian Xiu and Paul H. M. van Loosdrecht and Piotr Sur{\'o}wka and Takashi Oka and Zhe Wang},
  journal={Nature Communications},
  year={2019},
  volume={11}
}

• S. Kovalev, Renato M. A. Dantas, +12 authors Zhe Wang
• Published 5 November 2019
• Physics
• Nature Communications

Harmonic generation is a general characteristic of driven nonlinear systems, and serves as an efficient tool for investigating the fundamental principles that govern the ultrafast nonlinear dynamics. Here, we report on terahertz-field driven high-harmonic generation in the three-dimensional Dirac semimetal Cd3As2 at room temperature. Excited by linearly-polarized multi-cycle terahertz pulses, the third-, fifth-, and seventh-order harmonic generation is very efficient and detected via time-resolved spectroscopic techniques. The observed harmonic radiation is further studied as a function of pump-pulse fluence. Their fluence dependence is found to deviate evidently from the expected power-law dependence in the perturbative regime. The observed highly non-perturbative behavior is reproduced based on our analysis of the intraband kinetics of the terahertz-field driven nonequilibrium state using the Boltzmann transport theory. Our results indicate that the driven nonlinear kinetics of the Dirac electrons plays the central role for the observed highly nonlinear response. The mechanism and scaling of high harmonic generation in solids is a highly compelling ongoing area of research. Here the authors show a non-perturbative behavior of HHG in terahertz regime from 3D Dirac semimetal, Cd3As2, at room temperature, and reveal the underlying nonlinear kinetics.