Million-Atom Pseudopotential Calculation of {Gamma}-{ital X} Mixing in GaAs/AlAs Superlattices and Quantum Dots
- National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)
We have developed a {open_quotes}linear combination of bulk bands{close_quotes} method that permits atomistic, pseudopotential electronic structure calculations for {approximately}10{sup 6} atom nanostructures. Application to (GaAs){sub n}/(AlAs){sub n} (001) superlattices (SL{close_quote}s) reveals even-odd oscillations in the {Gamma}-X coupling magnitude V{sub {Gamma}X}(n), which vanishes for n=odd, even for {ital abrupt} and {ital segregated} SL{close_quote}s, respectively. Surprisingly, in contrast with recent expectations, 0D quantum dots are found here to have a {ital smaller} {Gamma}-X coupling than equivalent 2D SL{close_quote}s. Our analysis shows that for large quantum dots this is largely due to the existence of level repulsion from {ital many} X states. {copyright} {ital 1997} {ital The American Physical Society}
- Research Organization:
- National Renewable Energy Laboratory
- DOE Contract Number:
- AC36-83CH10093
- OSTI ID:
- 541967
- Journal Information:
- Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 14 Vol. 78; ISSN 0031-9007; ISSN PRLTAO
- Country of Publication:
- United States
- Language:
- English
Similar Records
Identity of the conduction-band minimum in (AlAs) sub 1 /(GaAs) sub 1 (001) superlattices: Intermixing-induced reversal of states
Free-standing versus AlAs-embedded GaAs quantum dots, wires, and films: The emergence of a zero-confinement state