Temperature dependence of energies and broadening parameters of the band-edge excitons of ? single crystals

We have measured the temperature dependence of the spectral features in the vicinity of direct band-edge excitonic transitions of single crystals from 25 to 300 K using piezoreflectance (PzR). From a detailed lineshape fit of the PzR spectra, the energies and broadening parameters of the A and B excitons have been determined accurately. The origin of these excitonic transitions is discussed. The transition energies and their splittings vary smoothly with the tungsten composition x, indicating that the natures of the direct band edges are similar for the compounds. In addition, the parameters that describe the temperature variation of the energies and broadening function of the excitonic transitions are evaluated and discussed.

[1]  C. Ho,et al.  Temperature dependence of energies and broadening parameters of the band-edge excitons of ReS 2 and ReSe 2 , 1997 .

[2]  Krystek,et al.  Temperature dependence of the direct gaps of ZnSe and Zn0.56Cd0.44Se. , 1996, Physical review. B, Condensed matter.

[3]  Steiner,et al.  Valence-band maximum in the layered semiconductor WSe2: Application of constant-energy contour mapping by photoemission. , 1996, Physical review. B, Condensed matter.

[4]  S. J. Li,et al.  thin films prepared by solid state reaction (induced by annealing) between the constituents in thin film form , 1996 .

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

[6]  J. M. Martín,et al.  Superlubricity of molybdenum disulphide. , 1993, Physical review. B, Condensed matter.

[7]  M. Yanagisawa,et al.  Adsorption and configuration of lubricant molecules on overcoat materials , 1993 .

[8]  M. Stroscio,et al.  Size dependence of the thermal broadening of the exciton linewidth in GaAs/Ga0.7Al0.3As single quantum wells , 1992 .

[9]  Gil,et al.  Piezomodulation spectroscopy: A powerful investigation tool of heterostructures. , 1991, Physical review. B, Condensed matter.

[10]  P. D. Fleischauer Fundamental aspects of the electronic structure, materials properties and lubrication performance of sputtered MoS2 films , 1987 .

[11]  Cardona,et al.  Temperature dependence of the dielectric function and interband critical points in silicon. , 1987, Physical review. B, Condensed matter.

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

[13]  Wold,et al.  Electronic structure of MoSe2, MoS2, and WSe2. I. Band-structure calculations and photoelectron spectroscopy. , 1987, Physical review. B, Condensed matter.

[14]  Haas,et al.  Electronic structure of MoSe2, MoS2, and WSe2. II. The nature of the optical band gaps. , 1987, Physical review. B, Condensed matter.

[15]  F. Lévy,et al.  Electrical and optical properties of MoSe2 films prepared by r.f. magnetron sputtering , 1985 .

[16]  M. R. Khan,et al.  Optical, electro-optical and transport properties of MoS2 , 1983 .

[17]  B. Parkinson,et al.  Detailed photocurrent spectroscopy of the semiconducting group VIB transition metal dichalcogenides , 1982 .

[18]  H. Tributsch,et al.  The Role of Carrier Diffusion and Indirect Optical Transitions in the Photoelectrochemical Behavior of Layer Type d‐Band Semiconductors , 1980 .

[19]  H. Hughes,et al.  Kramers-Kronig analysis of the reflectivity spectra of 2H-MoS2, 2H-MoSe2 and 2H-MoTe2 , 1979 .

[20]  G. Kuwabara,et al.  Excitons in VI B Transition Metal Dichalcogenides , 1978 .

[21]  A. R. McGurn,et al.  Antiferromagnetic-spin-flop critical field in MnxZn1-xF2 , 1978 .

[22]  D. Bullett,et al.  Electronic band structure and bonding in transition metal layered dichalcogenides by atomic orbital methods , 1978 .

[23]  Shoji Tanaka,et al.  Optical Phonon Modes and Localized Effective Charges of Transition-Metal Dichalcogenides , 1978 .

[24]  G. Kuwabara,et al.  Stress-optical studies of VI B transition metal dichalcogenides , 1978 .

[25]  W. Y. Liang,et al.  Kramers-Kronig analysis of the reflectivity spectra of 3R-WS2 and 2H-WSe2 , 1976 .

[26]  G. Weiser,et al.  Modulation Spectroscopy on MoS2, and MoSe2 , 1976 .

[27]  F. Raga,et al.  Excitons in molybdenum disulphide , 1975 .

[28]  B. Delmon,et al.  The role of cobalt and molybdenum sulphides in hydrodesulphurisation catalysts: A review☆ , 1974 .

[29]  John B. Pendry,et al.  Layer Method for Band Structure of Layer Compounds , 1973 .

[30]  L. Mattheiss Band Structures of Transition-Metal-Dichalcogenide Layer Compounds. , 1973 .

[31]  R. C. Weast CRC Handbook of Chemistry and Physics , 1973 .

[32]  T. K. Bergstresser,et al.  Electronic Structures of Semiconductor Alloys , 1970 .

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

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