Infrared Reflectance and Electrical Conductivity of ?-Ga2O3

Vı́llora, Encarnación G.; Morioka, Yoshiyuki; Atou, Toshiyuki; Sugawara, Takafumi; Kikuchi, Masae; Fukuda, Tsuguo

doi:10.1002/1521-396x(200209)193:1<187::aid-pssa187>3.0.co;2-1

Cited by 71 publications

(48 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In a second step, ε xx ,ε xy ,ε yy , and ε zz are analyzed simultaneously by Eqs. (21). As a result, we obtain all parameters for TO, LO, and LPP modes as well as for static and high-frequency dielectric constants.…”

Section: Ellipsometry Data and Model Dielectric Function Analysesmentioning

confidence: 99%

“…Víllora et al investigated single crystals of β-Ga 2 O 3 grown by the floating-zone technique [21]. Polarized reflectance spectra with an incidence angle of about 10…”

Section: -11mentioning

confidence: 99%

“…The TO mode frequencies obtained in our present work agree excellently with modes reported for A u symmetry in Ref. [21]. However, the TO mode frequencies for B u symmetry reported by Víllora et al deviate substantially from those found in this present work (Table II) (Table II).…”

Section: -11mentioning

confidence: 99%

“…Knowledge of phonon modes and free charge carrier parameters is not exhaustive for β-Ga 2 O 3 . Very few reports exist on experimental determination of phonon mode parameters and their anisotropy [21]. No report exists to our best knowledge which observes and describes coupling of phonon and free charge carrier modes.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Anisotropy, phonon modes, and free charge carrier parameters in monoclinicβ-gallium oxide single crystals

et al. 2016

View full text Add to dashboard Cite

We derive a dielectric function tensor model approach to render the optical response of monoclinic and triclinic symmetry materials with multiple uncoupled infrared and far-infrared active modes. We apply our model approach to monoclinic β-Ga 2 O 3 single-crystal samples. Surfaces cut under different angles from a bulk crystal, (010) and (201), are investigated by generalized spectroscopic ellipsometry within infrared and far-infrared spectral regions. We determine the frequency dependence of 4 independent β-Ga 2 O 3 Cartesian dielectric function tensor elements by matching large sets of experimental data using a point-by-point data inversion approach. From matching our monoclinic model to the obtained 4 dielectric function tensor components, we determine all infrared and far-infrared active transverse optic phonon modes with A u and B u symmetry, and their eigenvectors within the monoclinic lattice. We find excellent agreement between our model results and results of density functional theory calculations. We derive and discuss the frequencies of longitudinal optical phonons in β-Ga 2 O 3 . We derive and report density and anisotropic mobility parameters of the free charge carriers within the tin-doped crystals. We discuss the occurrence of longitudinal phonon plasmon coupled modes in β-Ga 2 O 3 and provide their frequencies and eigenvectors. We also discuss and present monoclinic dielectric constants for static electric fields and frequencies above the reststrahlen range, and we provide a generalization of the Lyddane-Sachs-Teller relation for monoclinic lattices with infrared and far-infrared active modes. We find that the generalized Lyddane-Sachs-Teller relation is fulfilled excellently for β-Ga 2 O 3 .

show abstract

Section: Ellipsometry Data and Model Dielectric Function Analysesmentioning

confidence: 99%

“…Víllora et al investigated single crystals of β-Ga 2 O 3 grown by the floating-zone technique [21]. Polarized reflectance spectra with an incidence angle of about 10…”

Section: -11mentioning

confidence: 99%

Section: -11mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Anisotropy, phonon modes, and free charge carrier parameters in monoclinicβ-gallium oxide single crystals

et al. 2016

View full text Add to dashboard Cite

show abstract

“…The growth of single crystals has been hindered, on the one hand, by the twinning affinity and cleavage nature of b-Ga 2 O 3 , on the other hand, by the high melting temperature of b-Ga 2 O 3 (2000 K). Different fluxes and transport agents have been tested [4][5][6][7][8], resulting in prismatic, rod, needle and [9,10], however, the most used technique has been the floating zone (FZ) [11,12], by which crystals of few mm wide and several cm long have been grown.…”

Section: Introductionmentioning

confidence: 99%