Atomic and electronic structure of Bi/GaAs(001)-alpha 2(2x4)

Usanmaz, D.
Ellialtıoğlu, Süleyman Şinasi
We report an ab initio pseudopotential calculation for the atomic and electronic structure of Bi/GaAs(001)-alpha 2(2 x 4). Three structural models with Bi coverages of Theta = 1/4 are considered, containing one Bi dimer or two Bi-As mixed dimers. According to our calculations for this coverage, the atomic model of the Bi/GaAs(001)-(2 x 4) reconstruction is similar to the alpha 2 structure of the clean GaAs(001)-(2 x 4) surface in which the top As dimer is replaced by a Bi dimer. This result is in agreement with the most recent scanning tunneling microscopy work.


Katırcıoğlu, Şenay; HALICIOGLU, T (Elsevier BV, 1993-04-01)
The ground-state total electronic energy of the Buckminsterfullerene (BF) and truncated dodecahedron (TD) models of C60 has been calculated using the empirical tight-binding (ETB) method. it was found that the BF model was energetically more stable than the TD model Of C60.
Composition-tuned band gap energy and refractive index in GaSxSe1-x layered mixed crystals
IŞIK, MEHMET; Hasanlı, Nızamı (Elsevier BV, 2017-04-01)
Transmission and reflection measurements on GaSxSe1-x mixed crystals (0 <= x <= 1) were carried out in the 400-1000 nm spectral range. Band gap energies of the studied crystals were obtained using the derivative spectra of transmittance and reflectance. The compositional dependence of band gap energy revealed that as sulfur (selenium) composition is increased (decreased) in the mixed crystals, band gap energy increases quadratically from 1.99 eV (GaSe) to 2.55 eV (GaS). Spectral dependencies of refractive i...
Thermal lattice scattering mobility and carrier effective mass in intrinsic Tl2InGaTe4 single crystals
Qasrawi, A. F.; Hasanlı, Nızamı (IOP Publishing, 2007-04-18)
Systematic structural, dark electrical resistivity and Hall coefficient measurements have been carried out on n- type Tl2InGaTe4 single crystals. The data from x- ray powder diffraction allowed determination of the tetragonal unit cell lattice parameters. Analysis of the electrical resistivity and carrier concentration, which was recorded in the temperature range 210 - 350 K, reveals the intrinsic type of conduction with an average energy band gap of 0.85 eV. The temperature- dependent Hall mobility was obs...
Electron-phonon short-range interactions mobility and p- to n-type conversion in TlGaS2 crystals
Qasrawi, AF; Hasanlı, Nızamı (Wiley, 2006-02-01)
The conductivity type conversion from p- to n-type at a critical temperature of 315 K in TlGaS2 crystals is observed through the Hall effect measurements in the temperature range of 200-350 K. The analysis of the temperature-dependent electrical resistivity, Hall coefficient and carrier concentration data reveals the extrinsic type of conduction with donor impurity levels that behave as acceptor levels when are empty. The data analysis allowed the calculation of hole and electron effective masses of 0.36m(0...
Hasanlı, Nızamı; CULFAZ, A (Wiley, 1995-01-01)
TlInSe2 and TlInTe2 crystallize in a tetragonal cell (space group 14/mcm) (Muller et al.). A primitive cell of these ternary crystals contains two formula units. All the Tl atoms in these compounds are univalent. The In atoms are trivalent being in a tetrahedral environment consisting of Se or Te atoms. InSe4 or InTe4 fragments of a unit cell form the chains extended along c-axis coinciding with [001] directions. Such chains are bonded to each other by Tl atoms.
Citation Formats
D. Usanmaz, M. ÇAKMAK, and S. Ş. Ellialtıoğlu, “Atomic and electronic structure of Bi/GaAs(001)-alpha 2(2x4),” JOURNAL OF PHYSICS-CONDENSED MATTER, pp. 0–0, 2008, Accessed: 00, 2020. [Online]. Available: