Doping-dependent intraband carrier dynamics in Landau-quantized graphene

Abstract

We investigate the intraband carrier dynamics in Landau-quantized graphene after an optical excitation with low-energetic terahertz pulses. Based on a microscopic theory, we calculate time-dependent differential transmission spectra reflecting the Landau-level dynamics. Our calculations reveal a strong dependence on the Fermi energy E F of the graphene sample as well as on the applied magnetic field B. We find that the pump pulse can lead to both absorption bleaching and absorption enhancement depending on B and the position of E F with respect to the resonant Landau-level transition. As a result, positive and negative contributions in differential transmission spectra appear, in good agreement with recent pump-probe measurements.

Carrier Dynamics in Graphene: Ultrafast Many‐Particle Phenomena

“…While the carrier dynamics in graphene has been intensively investigated over the last years, there have been only a few studies on the dynamics in Landau‐quantized graphene . The first experiment was performed by Plochocka et al.…”

“…While the carrier dynamics in graphene has been intensively investigated over the last years, there have been only a few studies on the dynamics in Landau-quantized graphene [17,30,53,57,[59][60][61]. The first experiment was performed by Plochocka et al in 2009 [30], where rather high-energetic Landau levels (n ∼ 100) have been investigated.…”

Controllable population dynamics in Landau-quantized graphene

“…In the past few years, much effort has been put towards studying carrier dynamics in Landau-quantized graphene under pulsed laser excitation 41 – 45 , The results showed that the Landau-level dynamics had a strong dependence on the Fermi energy and doping of the graphene sample, as well as the applied magnetic field. All these schemes are excited only by a pulsed laser without considering the continuous laser field.…”

Multiphonon resonance Raman scattering in Landau-quantized graphene

“…The non-equidistant Landau level (LL) separation is an unique property of graphene when the perpendicular magnetic field is presented, which displays a number of interesting optical properties [1,2], such as the selection rule of the emission of polarized light [3], a giant Faraday rotation [4]and generation of entangled photon states [5]. In particular, the LL separation can be tuned from the infrared to terahertz regimes by manipulating the external magnetic field, which may be used as the infrared and terahertz sources for many electric devices [6][7][8][9][10][11]. Therefore, the studies of the non-radiative relaxation channels between LLs, competing with the optical transitions processes, are of crucial for the exploration of optical properties in the Landau-quantized graphene (LQG).…”