Energetic Suppression of Decoherence in Exchange-Only Quantum Computation

Abstract

Universal quantum computation requiring only the Heisenberg exchange interaction and suppressing decoherence via an energy gap is presented. The combination of an always-on exchange interaction between the three physical qubits comprising the encoded qubit and a global magnetic field generates an energy gap between the subspace of interest and all other states. This energy gap suppresses decoherence. Always-on exchange couplings greatly simplify hardware specifications and the implementation of inter-logical-qubit gates. A controlled phase gate can be implemented using only three Heisenberg exchange operations all of which can be performed simultaneously.

4 pages, 4 figures

References in corpus (13)

• Few-Electron Quantum Dot Circuit with Integrated Charge Read-Out
• Tunable Non-local Spin Control in a Coupled Quantum Dot System
• Practical design and simulation of silicon-based quantum dot qubits
• Design and proof of concept for silicon-based quantum dot quantum bits
• Differential Charge Sensing and Charge Delocalization in a Tunable Double Quantum Dot
• Quantum Computing with an 'Always On' Heisenberg Interaction
• Experimental application of decoherence-free subspaces in a quantum-computing algorithm
• A Magnetic Resonance Realization of Decoherence-Free Quantum Computation
• Implementation of Universal Control on a Decoherence-Free Qubit
• Quantum computation with un-tunable couplings
• Simple Pulses for Universal Quantum Computation with a Heisenberg ABAB Chain
• Dispersive Manipulation of Paired Superconducting Qubits
• Scalable fault-tolerant quantum computation in DFS blocks

Cited by in corpus (18)

• Quantum Dot Cluster State Computing with Encoded Qubits
• Multi-qubit compensation sequences
• Quantum circuits based on coded qubits encoded in chirality of electron spin complexes in triple quantum dots
• Adiabatic topological quantum computing
• Read-out and Dynamics of the Qubit Built on Three Quantum Dots
• A Scalable Architecture for Coherence-Preserving Qubits
• A Simple Derivation of the Fong-Wandzura Pulse Sequence
• Thermal entanglement in a triple quantum dot system
• Simple operation sequences to couple and interchange quantum information between spin qubits of different kinds
• Improving Intrinsic Decoherence in Multi-Quantum-Dot Charge Qubits
• Theory of solid state quantum information processing
• Entanglement Sudden Death in a Quantum Memory
• Entanglement in a three spin system controlled by electric and magnetic field
• Tailoring Effective Exchange Interactions via Domain Walls in Coupled Heisenberg Rings
• Efficient Two-Qubit Pulse Sequences Beyond CNOT
• Automated searching for quantum subsystem codes
• Singlet-only Always-on Gapless Exchange Qubits with Baseband Control
• The Spin Density Matrix I: General Theory and Exact Master Equations