Quantum dots for quantum computing

• Grant number: 05/04592-3
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: September 01, 2006
• End date: August 05, 2008
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Gennady Gusev
• Grantee: Celso de Araujo Duarte
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The emergency of quantum computation as a new technology has been accompanied by intensive studies. On the theoretical viewpoint, there is a substantial advance, while in practice there is a lack of real devices. Arrays of quantum dots are the most promising candidates for such application, in which the quantum states of “up” and “down” spin may be associated to the Qbit (quantum bit) states 0 and 1. However, there is not yet an efficient method to control the spins of the individual quantum dots. We propose the use of the noticeable property of the variation of the electron Landé g factor along AlGaAs/GaAs parabolic quantum wells to control the spins by the application of external electric fields, without the use of coils and the application of external magnetic fields. For that we intend to produce lithographically patterned quantum dots in MBE grew parabolic quantum wells. We will study the effects of coupling of quantum dots and the control of the individual spins, in views to realize the Qbit. (AU)