The role of the excited impurity levels on the metal-non metal transition
Creators
- 1. Universidade Federal Fluminense, Niteroi (Brazil). Inst. de Fisica
Description
The electronic density of states for the impurity bands in doped semiconductors is calculated using the Green function method. The system is described by a Hamiltonian with local Coulomb interactions represented in a tight binding basis composed by two orbitals per site. The electronic correlation is treated in the CPA approximation. To calculate the configurational average for this structural disordered system a diagrammatic scheme is developed. It represents an extension of the Matsubara and Toyozawa method for the case of two hybridized bands in the presence of electronic correlation. The excited levels shown to play a crutial role in the understanding of the metal-non metal transition. This work represents an improvement of a previous result. The particular case of Si:P is analyzed. (Author)
Abstract (Portuguese)
Calcula-se a densidade de estados eletronicos para as bandas de impurezas em semicondutores dopados, usando o metodo das funcoes de Green. O sistema e descrito por um Hamiltoniano com interacoes Coulombianas locais, representado em uma base de ligacoes fortes composta por dois orbitais por sitio. A correlacao eletronica e tratada na aproximacao CPA. Desenvolve-se um esquema diagramatico, para o calculo das medias configuracionais para um sistema com desordem nao-diagonal. Este esquema representa uma extensao do metodo de Matsubara e Toyozawa para o caso de duas bandas hibridizadas na presenca de correlacao eletronica. Os niveis excitados tem um papel fundamental na compreensao da transicao metal-isolante. Este trabalho e um aprimoramento de um calculo anterior. E analizado o caso particular do Si:P. (Autor)Additional details
Publishing Information
- Journal Title
- Rev. Bras. Fis.
- Journal Volume
- especial)
- Series
- Rev. Bras. Fis.
- Journal Page Range
- 387-394
- ISSN
- 0374-4922
Conference
- Title
- 1. Brazilian School on Semiconductor Physics.
- Dates
- 31 Jan - 11 Feb 1983.
- Place
- Campinas, SP (Brazil).
INIS
- Country of Publication
- Brazil
- Country of Input or Organization
- Brazil
- INIS RN
- 16079034
- Subject category
- S75: CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY;
- Resource subtype / Literary indicator
- Conference, Numerical Data
- Descriptors DEI
- COULOMB FIELD; ELECTRON CORRELATION; ELECTRONIC STRUCTURE; GREEN FUNCTION; HAMILTONIANS; IMPURITIES; PHASE TRANSFORMATIONS; PHOSPHORUS ADDITIONS; SEMICONDUCTOR MATERIALS; SILICON; THEORETICAL DATA
- Descriptors DEC
- CORRELATIONS; DATA; ELECTRIC FIELDS; ELEMENTS; FUNCTIONS; INFORMATION; MATERIALS; MATHEMATICAL OPERATORS; NUMERICAL DATA; QUANTUM OPERATORS; SEMIMETALS