Spectroscopic ellipsometry investigation of optical properties of beta-Ga2S3 single crystals

Işık, Mehmet
Hasanlı, Nızamı
Gasanova, L.
Ga2S3 single crystals were studied by x-ray diffraction (XRD), energy dispersive spectroscopy and spectroscopic ellipsometry measurements. XRD pattern of the sample is well-matched with reported hexagonal structure of beta-Ga2S3 . The spectra of real and imaginary parts of complex dielectric function (epsilon = epsilon(1) + epsilon(2)) and refractive index (N = n + ik) were plotted in the 1.2-6.2 eV range according to results of ellipsometric data. The e 2 -spectrum and analyses of absorption coefficient pointed out that studied sample has band gap energy of 2.48 eV which is consistent with that of beta-Ga(2)S(3)2. Critical point energies of beta-Ga2S3 were also reported in the present study.


Optical properties of (Ga2Se3)(0.)(75) - (Ga2S3)(0.)(25) single crystals by spectroscopic ellipsometry
Işık, Mehmet; Hasanlı, Nızamı; Gasanova, L. (Elsevier BV, 2019-05-01)
Structural and optical properties of 75 mol % Ga2Se3 - 25 mol % Ga2S3 system of single crystals were investigated by experimental techniques of x-ray diffraction (XRD), energy dispersive spectroscopy, Raman spectroscopy and ellipsometry. XRD pattern indicated that the studied compound has crystalline nature with cubic structure. Vibrational modes in the crystal were revealed using Raman spectroscopy experiments in the 90-450 cm(-1) frequency range and nine modes were observed in the spectrum. Ellipsometry m...
Composition-tuned optical absorption and luminescence of TlGaxIn1-xS2 layered mixed crystals at T=10 K
Hasanlı, Nızamı (Elsevier BV, 2018-10-01)
Transmittance on TlGaxIn1-xS2 mixed crystals (0 <= x <= 1) was carried out in the 2.35-2.75 eV photon energy range at T = 10 K. Band gap energies of crystals were obtained utilizing the derivative spectra of transmittance and photon energy dependence of absorption coefficient. The dependence of direct band gap energy on composition at T = 10 K revealed that as gallium composition is elevated in the mixed crystals, the direct band gap energy increases from 2.56 to 2.67 eV.
Optical parameters of anisotropic chain-structured Tl2InGaTe4 crystals by spectroscopic ellipsometry
IŞIK, MEHMET; Hasanlı, Nızamı (Elsevier BV, 2016-01-01)
Spectroscopic ellipsometry measurements were performed on Tl2InGaTe4 single crystals in the 1.2-6.2 eV range for orientations of electric field, parallel (E//c) and perpendicular (E perpendicular to c) to optic axis c. Spectral dependence of optical parameters; real and imaginary components of the dielectric function, refractive index and extinction coefficient were obtained from the analyses of experimental data using an ambient-substrate optical model. The analysis of the absorption data calculated using ...
Radiative donor-acceptor pair recombination in TlInS2 single crystals
Aydinli, A; Hasanlı, Nızamı; Yilmaz, I; Serpenguzel, A (IOP Publishing, 1999-07-01)
Photoluminescence (PL) spectra of TlInS2 layered single crystals were investigated in the 500-860 nm wavelength region and in the 11.5-100 K temperature range. We observed two PL bands centred at 515 nm (2.41 eV, A band) and 816 nm (1.52 eV, B band) at T = 11.5 K and an excitation intensity of 7.24 FV cm(-2). A detailed study of the A band was carried out as a function of temperature and excitation laser intensity. A red shift of the A band position was observed for both increasing temperature and decreasin...
Optical Modulation With Silicon Microspheres
Yüce, Emre; Serpenguzel, Ali (Institute of Electrical and Electronics Engineers (IEEE), 2009-10-15)
In this letter, a silicon microsphere coupled to a silica optical fiber half coupler has been characterized for electrooptical modulation in the L-band at 1.55 mu m. Electrooptical modulation of the transmitted and the 90 degrees elastic scattered signals for both the TE and the TM polarizations of the microsphere resonances has been observed.
Citation Formats
M. Işık, N. Hasanlı, and L. Gasanova, “Spectroscopic ellipsometry investigation of optical properties of beta-Ga2S3 single crystals,” OPTICAL MATERIALS, pp. 95–99, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42351.