Ultrafast terahertz Faraday rotation in graphene

Abstract

Terahertz (THz) Faraday rotation measurements were performed to investigate carrier dynamics in p-type Chemical vapor deposition (CVD) graphene. We used static and time-resolved polarization-sensitive THz transmission measurements in a magnetic field to probe free carriers in GaAs, InP, and Graphene. Static measurements probe the equilibrium carrier density and momentum scattering rate. Time-resolved (optical pump/THz probe) measurements probe the change in these quantities following photoexcitation. In a typical CVD graphene sample, we found that 0.5 ps following photoexcitation with 1 × 1013 photons/cm2 pulses at 800 nm the effective hole scattering time decreased from 37 fs to 34.5 fs, while the carrier concentration increased from 2.0 × 1012 cm−2 to 2.04 × 1012 cm−2, leading to a transient decrease in the conductivity of the film.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 01, 2014
Source ID
10.1063/1.4903212

Entities

People

  • B. A. Alebachew
  • J. T. Robinson
  • James Heyman
  • M. D. Nguyen
  • R. F. Foo Kune

Organizations

  • Macalester College
  • National Science Foundation
  • Office of Naval Research
  • United States Naval Research Laboratory

Tags

Fields of Study

  • Materials science
  • Physics

Readers

  • Nanoscale Plasmonic Nanotechnology
  • Optical Physics and Photonics.
  • Semiconductor Device Technology

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene