Optical study of the structural change in ReS2 single crystals using polarized thermoreflectance spectroscopy.

In this report the optical properties of ReS2 are characterized using polarized thermoreflectance (PTR) measurements in the temperature range between 25 and 300 K. Single crystals of ReS2 were grown by chemical vapor transport method using Br2 as a transport agent. Crystal morphologies of the as-grown rhenium disulfides were shown to possess two different kinds of the structural phases after crystallization. Observing in detail on the crystallized solids, the crystal phases can be essentially divided into two distinct types of normal triclinic layer and tetragonal structure. The PTR experiments were done with optical polarizations along and perpendicular to the crystals' b-axis for both layer and tetragonal crystals. From the experimental analyses of PTR measurements the occurrence of structural change in ReS2 is mostly probable caused by the atomic bonding deformation along -axis, which is parallel to the Re4 parallelogram consisted diamond chains. Temperature dependences of the band-edge transitions for the different structural phases of ReS2 are analyzed. The parameters that describe temperature variations of the transition energies and broadening parameters for both layered and tetragonal ReS2 are evaluated and discussed.

[1]  Cardona,et al.  Temperature dependence of the dielectric function and the interband critical points of InSb. , 1985, Physical review. B, Condensed matter.

[2]  S. Harris,et al.  Catalysis by transition metal sulfides: The relation between calculated electronic trends and HDS activity , 1984 .

[3]  C. Ho,et al.  Practical thermoreflectance design for optical characterization of layer semiconductors , 2004 .

[4]  C. Jacobsen,et al.  Rhenium(IV) sulfide nanotubes. , 2002, Journal of the American Chemical Society.

[5]  J. Marzik,et al.  Photoelectronic properties of ReS2 and ReSe2 single crystals , 1984 .

[6]  G. Wiegers,et al.  The crystal structure of some rhenium and technetium dichalcogenides , 1996 .

[7]  J. Wilson,et al.  The transition metal dichalcogenides discussion and interpretation of the observed optical, electrical and structural properties , 1969 .

[8]  C. Ho,et al.  Optical absorption of ReS2 and ReSe2 single crystals , 1997 .

[9]  M. Cardona,et al.  Interband critical points of GaAs and their temperature dependence. , 1987, Physical review. B, Condensed matter.

[10]  F. Jellinek,et al.  The dichalcogenides of technetium and rhenium , 1971 .

[11]  D. Lin,et al.  Piezoreflectance study of InP near the absorption edge , 1996 .

[12]  C. Ho,et al.  Absorption-edge anisotropy in ReS 2 and ReSe 2 layered semiconductors , 1998 .

[13]  C. Ho,et al.  In-plane anisotropy of the optical and electrical properties of ReS2 and ReSe2 layered crystals , 2001 .

[14]  C. Ho,et al.  Piezoreflectance study of the band-edge excitons of ReS2 , 1997 .

[15]  K. O'Donnell,et al.  Temperature dependence of semiconductor band gaps , 1991 .

[16]  P. Yen,et al.  Photoreflectance study of the excitonic transitions of rhenium disulphide layer compounds , 2002 .

[17]  Malcolm L. H. Green,et al.  The formation of ReS2 inorganic fullerene-like structures containing Re4 parallelogram units and metal-metal bonds. , 2002 .

[18]  Y. P. Varshni.  Temperature dependence of the energy gap in semiconductors , 1967 .

[19]  K. Tiong,et al.  Crystal structure and band-edge transitions of ReS2−xSex layered compounds , 1999 .

[20]  Fred H. Pollak,et al.  Modulation spectroscopy of semiconductors: bulk/thin film, microstructures, surfaces/interfaces and devices , 1993 .

[21]  M. Lux‐Steiner,et al.  Optical properties of the layered transition-metal-dichalcogenide ReS2 : anisotropy in the van der Waals plane , 1993 .

[22]  F. P. Koffyberg,et al.  Interband Transitions of Semiconducting Oxides Determined from Photoelectrolysis Spectra. , 1979 .

[23]  Rolf E. Hummel,et al.  Alloys and Compounds , 1998 .

[24]  C. Ho,et al.  Polarization sensitive behaviour of the band-edge transitions in ReS2 and ReSe2 layered semiconductors , 2004 .