Photogalvanic effect in Weyl semimetals

التفاصيل البيبلوغرافية
العنوان: Photogalvanic effect in Weyl semimetals
المؤلفون: König, E. J., Xie, H. -Y., Pesin, D. A., Levchenko, A.
المصدر: Phys. Rev. B 96, 075123 (2017)
سنة النشر: 2017
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Mesoscale and Nanoscale Physics
الوصف: We theoretically study the impact of impurities on the photogalvanic effect (PGE) in Weyl semimetals with weakly tilted Weyl cones. Our calculations are based on a two-nodes model with an inversion symmetry breaking offset and we employ a kinetic equation approach in which both optical transitions as well as particle-hole excitations near the Fermi energy can be taken into account. We focus on the parameter regime with a single photoactive node and control the calculation in small impurity concentration. Internode scattering is treated generically and therefore our results allow to continuously interpolate between the cases of short range and long range impurities. We find that the time evolution of the circular PGE may be nonmonotonic for intermediate internode scattering. Furthermore, we show that the tilt vector introduces three additional linearly independent components to the steady state photocurrent. Amongst them, the photocurrent in direction of the tilt takes a particular role inasmuch it requires elastic internode scattering or inelastic intranode scattering to be relaxed. It may therefore be dominant. The tilt also generates skew scattering which leads to a current component perpendicular to both the incident light and the tilt. We extensively discuss our findings and comment on the possible experimental implications.
Comment: 6 pages + appendix, 4 figures
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevB.96.075123
URL الوصول: http://arxiv.org/abs/1705.03903
رقم الأكسشن: edsarx.1705.03903
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevB.96.075123