Spin-based all-optical quantum computation with quantum dots: Understanding and suppressing decoherence

Journal Article · Tue Jul 01 04:00:00 EDT 2003 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.68.012310· OSTI ID:20639876

Calarco, T ^[1]; Datta, A ^[2]; Fedichev, P; Zoller, P ^[3]; Pazy, E ^[4]

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1. NIST, Gaithersburg, Maryland 20899-8423, USA and ECT, I-38050 Villazzano (Tunisia), (Italy)
2. Department of Electrical Engineering, Indian Institute of Technology, Kanpur 208016, (India)
3. Institut fuer Theoretische Physik, Universitaet Innsbruck, A-6020 Innsbruck, (Austria)
4. Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105, (Israel)

We present an all-optical implementation of quantum computation using semiconductor quantum dots. Quantum memory is represented by the spin of an excess electron stored in each dot. Two-qubit gates are realized by switching on trion-trion interactions between different dots. State selectivity is achieved via conditional laser excitation exploiting Pauli exclusion principle. Read out is performed via a quantum-jump technique. We analyze the effect on our scheme's performance of the main imperfections present in real quantum dots: exciton decay, hole mixing, and phonon decoherence. We introduce an adiabatic gate procedure that allows one to circumvent these effects and evaluate quantitatively its fidelity.

• OSTI ID: 20639876
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 1 Vol. 68; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
74 ATOMIC AND MOLECULAR PHYSICS
ELECTRONS
EXCITATION
EXCITONS
IMPLEMENTATION
INFORMATION THEORY
LASER RADIATION
MIXING
PAULI PRINCIPLE
PERFORMANCE
PHONONS
QUANTUM DOTS
QUANTUM MECHANICS
READOUT SYSTEMS
SEMICONDUCTOR MATERIALS
SPIN
VISIBLE RADIATION