نتایج جستجو برای: band structure

تعداد نتایج: 1673409  

پایان نامه :دانشگاه تربیت معلم - تهران - دانشکده علوم 1393

in this thesis, structural, electronical, and optical properties of inverse pervskite(ca3pbo) in cubic phase have been investigated.the calculation have been done based on density functional theory and according to generalized gradiant approximate (gga) as correlating potential. in order to calculate the configurations, implementing in the wien2k code have been used from 2013 version. first of ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده علوم 1387

boron nitride semiconducting zigzag swcnt, $b_{cb}$$n_{cn}$$c_{1-cb-cn}$, as a potential candidate for making nanoelectronic devices was examined. in contrast to the previous dft calculations, wherein just one boron and nitrogen doping configuration have been considered, here for the average over all possible configurations, density of states (dos) was calculated in terms of boron and nitrogen ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه ارومیه 1377

the methods which are used to analyze microstrip antennas, are divited into three categories: empirical methods, semi-empirical methods and full-wave analysis. empirical and semi-empirical methods are generally based on some fundamental simplifying assumptions about quality of surface current distribution and substrate thickness. thses simplificatioms cause low accuracy in field evaluation. ful...

Journal: :international journal of nano dimension 0
t. farajollahpour department of physics, faculty of science, i.h.u tehran, iran. a. rezvani department of physics, faculty of science, i.h.u tehran, iran. m. r. khodarahmi department of physics, faculty of science, i.h.u tehran, iran. m. arasteh department of physics, faculty of science, i.h.u tehran, iran.

in this paper energy bands and berry curvature of graphene was studied. desired hamiltonian regarding the next-nearest neighbors obtained by tight binding model. by using the second quantization approach, the transformation matrix is calculated and the hamiltonian of system is diagonalized. with this hamiltonian, the band structure and wave function can be calculated. by using calculated wave f...

Journal: :international journal of nano dimension 0
s. jalili department of chemistry, k. n. toosi university of technology,tehran, iran. computational physical sciences research laboratory, department of nano-science, institute for studies in theoretical physics and mathematics (ipm),tehran, iran r. vaziri department of chemistry, k. n. toosi university of technology,tehran, iran.

first principle calculations were performed using density functional theory within the local spin density approximation (lsda) to understand the electronic properties of au(100)+tbt system and compare the results with au(100) and bulk au properties. band structure, the total dos and charge density for these materials are calculated. we found that the homo for au(100)+tbt becomes broader than au...

Journal: :physical chemistry research 2013
mahmood moradi mohammad rostami

the electronic and magnetic properties of the hypothetical compounds of mc (m=al, ga and in) are investigated by using first-principle calculations and pseudopotential plane wave self-consistent field method based on density functional theory. in order to find the most stable phase of mc (m=al, ga and in), we study them in zinc-blende (zb), rocksalt (rs), wurtzite and nias crystal structures. w...

Journal: :chemistry of solid materials 0
seyed javad mousavi

we have investigated the electronic structure and thermodynamic properties of supercell of the -al2o3 by first-principles calculation in framework of density functional theory (dft) and full potential linearized augmented plane wave (fp-lapw) with generalized gradient approximation (gga) and by quasi-harmonic debye model. our calculated value for direct band gap of α-al2o3 is 7.2 ev which is v...

In this research, we have studied the photonic band structure, optical properties and thermal emission spectrum of 2D Silicon photonic crystal with hexagonal structure. The band structure, band gap map and the gap size versus radius have been calculated by plane wave expansion method. The maximum band gap size of TE (TM) polarization and the complete gap size are 51% (20%) and 17% at air hole r...

Journal: :iranian journal of science and technology (sciences) 2013
m. aryadoust

the purpose of this paper is the generalization of structure factor for rods by polygon section in two dimensional phononic crystals. if we use the plane wave expansion method (pwe) for the propagation of acoustic waves in 2d phononic crystals, structure factor will be an important quantity. in order to confirm the obtained relations, we have calculated the band structure for xy and z vibration...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید