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Asymmetric quantum dots are coupled through
an applied electric field
E. A. Stinaff et al, Science 311, 636 (2006).
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Why CQDs?
Coupling With Applied Field
Fabrication
Coupling Mechanism
Scaling Up
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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)
1 2 3
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Asymmetric pair of InAs Quantum Dots
Exciton Notation:
Indirect
Resonance
Direct
Coupling = Resonance = Anticrossing Condition: Optical Excitation,
Tunneling, Indirect Transitions Possible
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Bottom Layer InAs QDs
GaAs Tunneling Barrier
Top Layer InAs QDs
Asymmetric QDs by Design
Distinct Optical Transitions
Distinguishing Individual QDs
…Scalability
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Model Without
Tunneling & Spin
1 2 3Model WithTunneling &
Spin
Experimental
SpectrumResonance At
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