title: Polarized Raman scattering study of kesterite type Cu2ZnSnS4 single crystals.
abstract: A non-destructive Raman spectroscopy has been widely used as a complimentary method to X-ray diffraction characterization of Cu2ZnSnS4 (CZTS) thin films, yet our knowledge of the Raman active fundamental modes in this material is far from complete. Focusing on polarized Raman spectroscopy provides important information about the relationship between Raman modes and CZTS crystal structure. In this framework the zone-center optical phonons of CZTS, which is most usually examined in active layers of the CZTS based solar cells, are studied by polarized resonant and non-resonant Raman spectroscopy in the range from 60 to 500 cm(-1) on an oriented single crystal. The phonon mode symmetry of 20 modes from the 27 possible vibrational modes of the kesterite structure is experimentally determined. From in-plane angular dependences of the phonon modes intensities Raman tensor elements are also derived. Whereas a strong intensity enhancement of the polar E and B symmetry modes is induced under resonance conditions, no mode intensity dependence on the incident and scattered light polarization configurations was found in these conditions. Finally, Lyddane-Sachs-Teller relations are applied to estimate the ratios of the static to high-frequency optic dielectric constants parallel and perpendicular to c-optical axis.
authors.affiliation: Institute of Applied Physics, Academy of Sciences of Moldova, Chisinau, MD 2028, Moldova.|IREC, Catalonia Institute for Energy Research, Sant Adrià del Besòs (Barcelona), 08930, Spain.
authors.forename: Maxim
authors.initials: M
authors.lastname: Guc
authors.affiliation: Helmholtz Zentrum Berlin fur Materialien und Energie, Berlin, D-14109, Germany.
authors.forename: Sergiu
authors.initials: S
authors.lastname: Levcenko
authors.affiliation: Department of Chemistry, Belarusian State University of Informatics and Radioelectronics, Minsk, Belarus.
authors.forename: Ivan V
authors.initials: IV
authors.lastname: Bodnar
authors.affiliation: IREC, Catalonia Institute for Energy Research, Sant Adrià del Besòs (Barcelona), 08930, Spain.
authors.forename: Victor
authors.initials: V
authors.lastname: Izquierdo-Roca
authors.affiliation: IREC, Catalonia Institute for Energy Research, Sant Adrià del Besòs (Barcelona), 08930, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Fontane
authors.affiliation: Department of Chemistry, Belarusian State University of Informatics and Radioelectronics, Minsk, Belarus.
authors.forename: Larisa V
authors.initials: LV
authors.lastname: Volkova
authors.affiliation: Institute of Applied Physics, Academy of Sciences of Moldova, Chisinau, MD 2028, Moldova.
authors.forename: Ernest
authors.initials: E
authors.lastname: Arushanov
authors.affiliation: IREC, Catalonia Institute for Energy Research, Sant Adrià del Besòs (Barcelona), 08930, Spain.|IN2UB, Departament d'Electrònica, Universitat de Barcelona, Barcelona, 08028, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Pérez-Rodríguez