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arXiv · 0906.1104

Slowing hot carrier relaxation in graphene using a magnetic field

P. Plochocka·P. Kossacki·A. Golnik·T. Kazimierczuk·C. Berger·W. A. de Heer·M. Potemski
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Abstract

A degenerate pump--probe technique is used to investigate the non equilibrium carrier dynamics in multi--layer graphene. Two distinctly different dynamics of the carrier relaxation are observed. A fast relaxation ($\sim 50$ fs) of the carriers after the initial effect of phase space filling followed by a slower relaxation ($\sim 4$ ps) due to thermalization. Both relaxation processes are less efficient when a magnetic field is applied at low temperatures which is attributed to the suppression of the electron-electron Auger scattering due to the non equidistant Landau level spacing of the Dirac fermions in graphene.

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P. Plochocka, P. Kossacki, A. Golnik, T. Kazimierczuk, C. Berger, W. A. de Heer, M. Potemski. 2009-12-11. Slowing hot carrier relaxation in graphene using a magnetic field. https://doi.org/10.1103/physrevb.80.245415

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