Abnormal anti-Stokes Raman spectra of single walled carbon nanotubes raised from coherent anti-Stokes Raman scattering and optical cooling processes

作者：Baltog I^*; Baibarac M; Mihut L; Lefrant S

来源：Digest Journal of Nanomaterials and Biostructures, 2007, 2(1): 185-198.

• carbon nanotubes
• anti-Stokes Raman scattering
• CARS
• optical cooling

For the single-walled carbon nanotubes, the higher values of anti-Stokes/Stokes Raman intensity ratio (I(as)/I(s)) then the predictions of the Maxwell-Bolzmann formula indicates a CARS emission resulting from a wave mixing process between the incident laser light (omega(l)) and Stokes Raman light (omega(s)) generated by a SERS mechanism. The weaker value of (I(as)/Is) observed at resonant excitation of semiconducting nanotubes in the E(22)(S) van Hove state, relates a quantum cooling process occurred during the relaxation of the E22S excited state in two steps-by phonon emission from E(22)(S) to E(11)(S) followed by a spontaneous luminescence emission at E(11)(S).

• 出版日期2007-3