BAND STRUCTURE AND MAGNETIC PROPERTIES OF CUBIC CRYSTALS INXGA1-XN: AB INITIO CALCULATIONS
Abstract and keywords
Abstract (English):
Band structure of solid solutions InxGa1-xN with sphalerite struc-ture and with considerable percentage of indium (x = 0.25; 0.5; 0.6; 0.7; 0.75; 0.9; 0.95; 0.97; 0.99; 1,0 ) is calculated using the density-functional theory (DFT) and the cluster version of the local coherent potential method within the frame of the multiple scatter-ing theory. The electron structure of the ternary solutions of InxGa1-xN in sphalerite crystallographic modification is compared; the interpretation of their features is given. The concentration de-pendence on the energy gap for the entire variation range of the indium content in the solution is obtained. The spin polarization effect of the states of In, Ga, and N for the alloys with the consid-erable percentage of In, as well as the transition of the ternary solu-tions of In0.75Ga0.25N into the of magnetic semiconductor state is found out. The magnetic moments of In, Ga, and N atoms, and the saturation magnetization in InxGa1-xN semiconductor system are determined.

Keywords:
band structure, magnetic moment, valence band, band gap, density of electronic states.
Text

The semiconductor solid solutions InxGa1-xN are the most promising materials for optoelectronics to obtain the blue and green light-emitting diodes which are used for high-density optical storage of information and high-power devices, for blue lasers for instance. The extraordinary property of these materials is the ability to operate over a wide temper-ature range and the insensitivity to X-ray irradiation [1, 2]. By varying of the indium percentage one can manage the value of the energy gap in the range from 1.92 eV (c-InN) [3] upto 3.2 eV (c-GaN) [3] that gives the opportunity to use these materials in various parts of spectrum [4, 5]. For the far ultraviolet region (240-300 nм) the semiconductor materials based on InxGa1-xN (0,5< x < 1) crystals are of high interest.

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