Controlled exchange interaction for quantum logic operations with spin qubits in coupled quantum dots
arXiv:cond-mat/0612662 · doi:10.1103/PhysRevA.76.032302
Abstract
A two-electron system confined in two coupled semiconductor quantum dots is investigated as a candidate for performing quantum logic operations on spin qubits. We study different processes of swapping the electron spins by controlled switching on/off the exchange interaction. The resulting spin swap corresponds to an elementary operation in quantum information processing. We perform a direct time evolution simulations of the time-dependent Schroedinger equation. Our results show that -- in order to obtain the full interchange of spins -- the exchange interaction should change smoothly in time. The presence of jumps and spikes in the corresponding time characteristics leads to a considerable increase of the spin swap time. We propose several mechanisms to modify the exchange interaction by changing the confinement potential profile and discuss their advantages and disadvantages.
References in corpus (22)
- Quantum Computation with Quantum Dots
- Single-shot read-out of an individual electron spin in a quantum dot
- Coupled quantum dots as quantum gates
- Two-Bit Gates are Universal for Quantum Computation
- Reliable Quantum Computers
- Universal Quantum Computation with the Exchange Interaction
- Electron Spin Resonance Transistors for Quantum Computing in Silicon-Germanium Heterostructures
- Few-Electron Quantum Dot Circuit with Integrated Charge Read-Out
- Zeeman energy and spin relaxation in a one-electron quantum dot
- Design and proof of concept for silicon-based quantum dot quantum bits
- Practical design and simulation of silicon-based quantum dot qubits
- Double-Occupancy Errors, Adiabaticity, and Entanglement of Spin-Qubits in Quantum Dots
- Quantum Information is Physical
- Quantum Information Processing with Ferroelectrically Coupled Quantum Dots
- Controlling Spin Qubits in Quantum Dots
- Non-destructive measurement of electron spins in a quantum dot
- Generation of maximum spin entanglement induced by cavity field in quantum-dot systems
- Electron spin and charge switching in a coupled quantum dot quantum ring system
- Quantum computing with spin qubits in semiconductor structures
- Long-lived memory for electronic spin in a quantum dot: Numerical analysis
- Spintronics and Quantum Computing: Switching Mechanisms for Qubits
- Fast quantum computing with semiconductor quantum dots in a microcavity