Fidelity of Optically Controlled Single- and Two-Qubit Operations on Coulomb-Coupled Quantum Dots

Abstract

We investigate the effect of the Coulomb interaction on the applicability of quantum gates on a system of two Coulomb-coupled quantum dots. We calculate the fidelity for a single- and a two-qubit gate and the creation of Bell states in the system. The influence of radiative damping is also studied. We find that the application of quantum gates based on the Coulomb interaction leads to significant input state-dependent errors which strongly depend on the Coulomb coupling strength. By optimizing the Coulomb matrix elements via the material and the external field parameters, error rates in the range of $10^{-3}$ can be reached. Radiative dephasing is a more serious problem and typically leads to larger errors on the order of $10^{-2}$ for the considered gates. In the specific case of the generation of a maximally entangled Bell state, error rates in the range of $10^{-3}$ can be achieved even in the presence of radiative dephasing.

arXiv comment8 pages, 10 figures; final version

References in corpus (13)

• Quantum Computation with Quantum Dots
• Quantum-Information Processing with Semiconductor Macroatoms
• Size-dependent fine-structure splitting in self-organized InAs/GaAs quantum dots
• Theory of Quantum Optical Control of Single Spin in a Quantum Dot
• Optical Schemes for Quantum Computation in Quantum Dot Molecules
• Electro-optical properties of semiconductor quantum dots: Application to quantum information processing
• Anticrossings in Foerster Coupled Quantum Dots
• Theory of Fast Quantum Control of Exciton Dynamics in Semiconductor Quantum Dots
• Excitonic exchange effects on the radiative decay time of monoexcitons and biexcitons in quantum dots
• Optically-controlled logic gates for two spin qubits in vertically-coupled quantum dots
• Quantum Computing with Spin Qubits Interacting Through Delocalized Excitons: Overcoming Hole Mixing
• Interplay and optimization of decoherence mechanisms in the optical control of spin quantum bits implemented on a semiconductor quantum dot
• Precision of single-qubit gates based on Raman transitions

Cited by in corpus (1)

• Dynamics and relaxation of sp biexcitons in disk-shaped quantum dots