Prof. Feile
Raman and Brillouin spectroscopy

The main methods used in the working group were Raman- and Brillouin-spectroscopy. Both are optical spectral techniques with different resolution. The frequency shifting of the incident light while interacting with the excitations of different systems in condensed matter.

Raman spectroscopy

Raman spectroscopy works for the frequency intervall from 10cm-1 to 5000cm-1 which corresponds to energies from 0.001eV to 0.6eV. That covers the regime of molceular and lattice vibrations.

Brillouin spectroscopy

For smaller frequencies of 500 MHz to 30 GHz, i.e., energies from 2μeV to 120μeV, Brillouin spectroscopy is used. For instance it is possible to study the propagation of high frequency accustic waves (hypersound). For even lower excitation frequencies one can use ultrasonic or laser reflectometric methods.

Fields of activity and methods

The group is equipped with a double-grating monochromator for the Raman spectroscopy and a modern tandem Fabry Perot interferometer for Brillouin investigations. These devices are supplemented with an Ar-ion laser as well as a NdYAG laser as sources of light, various cryostats, 'closed cycle'-devices for taking the temperature range from approx. 2,5 to 300 K and a diamond high pressure cell for investigations under the pressure of up to approx. 30 GPa.

  1. Schneider, J.J.; Maksimova, N.I.; Engstler, J.; Joshi, R.; Schierholz, R.; Feile R.: Catalyst free growth of a carbon nanotube-alumina composite structure
    INORGANICA CHIMICA ACTA 361, 1770-1778 (2008)
  2. Li, R.; Feile, R,; Jakob, G.: An interface effect in c-oriented (Y/Pr)Ba2Cu3O7 Superlattices.
    J. Physics and Chemistry of Solids 58, 379 (1997)
  3. Light scattering in high-Tc (Y/Pr)Ba2Cu3O7 superlattices. Li, R.; Sherman, E.; Feile, R. in Studies of High Temperature Superconductors Vol. 22: Critical Current, Flux pinning & Optical Studies of High Temperature Superconductors ed. A.V. Narlikar, Nova Science Publishers, 1997
  4. Jung J., Bruchhäuser F., Feile R., Spiering H., and Gütlich P.: The cooperative spin transition in [FexZn1-x(ptz)6](BF4)2: I. Elastic properties – an oriented sample rotation study by Brillouin spectroscopy
    Z. v. Phys. B (condensed matter) 100, 517 (1996)
  5. Westerhoff, T.; Feile, R.: High-pressure Raman study of the N2 stretching vibration in argon-nitrogen mixtures at room temperature.
    Phys. Rev. B 54, 913 (1996)
  6. Westerhoff, T.; Wittig, A.; Feile, R.: High-pressure Raman scattering of the stretching mode in nitrogen along the 300-K isotherm.
    Phys. Rev. B 54, 14 (1996)
  7. Westerhoff, T.; Feile, R.: Single particle orientational potential for the N2 molecules in the cubic delta-phase of nitrogen.
    Z. Phys.B (condensed matter) 100, 417 (1996)
  8. Li, R.; Sherman, E.; Feile, R. ; Jakob, G.; Hahn, Th.; Adrian, H.: Charge transfer in high-Tc (Y/Pr)Ba2Cu3O7 superlattices.
    Phys. Rev. B 53, 6836 (1996)
  9. Sherman, E. Ya., Li, R., Feile, R.: Intensity of the B1g phonon Raman scattering in YBa2Cu3O7: comparison of normal and superconducting states
    Phys. Rev. B 52, 15757 (1995)
  10. Sherman, E.; Li, R.; Feile, R.: Interband Electron-Phonon Scattering in YBa2Cu3O7: the B1g Phonon Raman Scattering, and the Plane Oxygen Ions Interaction.
    Solid State Communication 94, 851 (1995)
  11. Sherman, E.; Li, R.; Feile, R.; Adrian, H.; Jakob, G.: Light Scattering Mechanism in High-Tc (Y/Pr)Ba2Cu3O7 Superlattices.
    J. Low Temp. Phys. 99, 263 (1995)
  12. Li, R.; Sherman, E.; Feile, R.; Adrian, H.; Jakob, G.; Hahn, Th: Light Scattering in a (Y/Pr)Ba2Cu3O7 superlattice and the intensity of a new Raman active phonon.
    Physica C 242, 46-54 (1995)
  13. Li, R.; Feile, R.; Jakob, G.; Hahn, Th.; Adrian, H: Confined and Extended Optical Phonons in an Ultrathin Layer Superconducting YBa2Cu3O7 /PrBa2Cu3O7
    Phys. Rev. B 51, 1322 (1995)