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Asymmetric quantum dots are coupled through an applied electric field. Coupled Quantum Dots Brittany Mcclinton EE C235 Nanofabrication 3/17/08. E. A. Stinaff et al, Science 311 , 636 (2006). Why CQDs? Coupling With Applied Field Fabrication Coupling Mechanism Scaling Up. 1. 2. 3.
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Asymmetric quantum dots are coupled through an applied electric field Coupled Quantum DotsBrittany McclintonEE C235 Nanofabrication 3/17/08 E. A. Stinaff et al, Science311, 636 (2006).
Why CQDs? Coupling With Applied Field Fabrication Coupling Mechanism Scaling Up
1 2 3 1 Scalable qubits Each dot represents a qubit 2 Long-lived Spin of unpaired electron or hole 3 Ultra-fast Optically excited states as auxiliary levels (laser pulses) Why CQDs? WHY NOT SQDs?
Asymmetric pair of InAs Quantum Dots Exciton Notation: Indirect Resonance Direct Coupling = Resonance = AnticrossingCondition: Optical Excitation, Tunneling, Indirect Transitions Possible Coupling with an Applied Field
Bottom Layer InAs QDs GaAs Tunneling Barrier Top Layer InAs QDs Asymmetric QDs by Design Fabrication
Model Without Tunneling & Spin 1 2 3 Coupling mechanism Model With Tunneling & Spin Experimental Spectrum Resonance At