Selected Applications
attoRAMAN
Electronics
scan controller and software
dedicated FPGA-based RAMAN controller providing coarse positioning and scanning signals for sample
positioning and scanning in x, y, and z direction; control software for extensive RAMAN signal data
acquisition and post processing
Options
sample holder upgrade
ASH/QE/4CX quick-exchange sample holder with 8 electrical contacts and integrated heater with
calibrated temperature sensor
Raman Spectroscopy on Graphene
The figure to the left shows magneto-Raman measurements recorded at 4 K
on an exfoliated single crystal of natural graphite with unprecedented spa-
tial resolution (approx. 0.5 μm), while sweeping the magnetic field from -9 T
to +9 T. The data were recorded on a single graphene flake and demonstrate
the crossing of the E2g phonon energy with the electron-hole separation
between the valence and conduction Landau levels (-N,+M) of the Dirac
cone. Resonant hybridization of the E2g phonon is a specific signature of
graphene flakes which display very rich Raman scattering spectra varying
strongly as function of magnetic field [1].
[1] C. Faugeras et al., Phys. Rev. Lett. 107, 036807 (2011); (attocube application labs, 2011; work in
cooperation with C. Faugeras, P. Kossacki, and M. Potemski, LNCM I - Grenoble, CNRS_UJF_UPS_INSA France)
Magneto-Raman Microscopy for Probing Local Material
Properties of Graphene
The combination of confocal Raman microscopy and magnetic fields at 4 K yields
the opportunity to investigate and tune the electron-phonon interaction in
graphene and few-layer graphene. In particular, excitations between Landau
levels can resonantl