title: Novel micro-Raman setup with tunable laser excitation for time-efficient resonance Raman microscopy and imaging.
abstract: We describe a micro-Raman setup allowing for efficient resonance Raman spectroscopy (RRS), i.e., mapping of Raman spectra as a function of tunable laser excitation wavelength. The instrument employs angle-tunable bandpass optical filters which are integrated into software-controlled Raman and laser cleanup filter devices. These automatically follow the excitation laser wavelength and combine tunability with high bandpass transmission as well as high off-band blocking of light. Whereas the spectral intervals which can be simultaneously acquired are bandpass limited to ~350 cm(-1), they can be tuned across the spectrum of interest to access all characteristic Raman features. As an illustration of performance, we present Raman mapping of single-walled carbon nanotubes (SWNTs): (i) in a small volume of water-surfactant dispersion as well as (ii) after deposition onto a substrate. A significant improvement in the acquisition time (and efficiency) is demonstrated compared to previous RRS implementations. These results may help to establish (micro) Raman spectral mapping as a routine tool for characterization of SWNTs as well as other materials with a pronounced resonance Raman response in the visible-near-infrared spectral region.
authors.affiliation: Karlsruhe Institute of Technology, Institute of Nanotechnology, 76021 Karlsruhe, Germany.
authors.forename: Ninette
authors.initials: N
authors.lastname: Stürzl
authors.forename: Sergei
authors.initials: S
authors.lastname: Lebedkin
authors.forename: Stefanie
authors.initials: S
authors.lastname: Klumpp
authors.forename: Frank
authors.initials: F
authors.lastname: Hennrich
authors.forename: Manfred M
authors.initials: MM
authors.lastname: Kappes
mesh_terms: D007834:Lasers; D037742:Nanotubes, Carbon / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000295:instrumentation / Q000379:methods*; D013501:Surface-Active Agents / Q000737:chemistry; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D037742:Nanotubes, Carbon; D013501:Surface-Active Agents; D014867:Water