A Scalable Architecture for Coherence-Preserving Qubits

Abstract

We propose scalable architectures for the coherence-preserving qubits introduced by Bacon, Brown, and Whaley [Phys. Rev. Lett. {\bf 87}, 247902 (2001)]. These architectures employ extra qubits providing additional degrees of freedom to the system. We show that these extra degrees of freedom can be used to counter errors in coupling strength within the coherence-preserving qubit and to combat interactions with environmental qubits. The presented architectures incorporate experimentally viable methods for inter-logical-qubit coupling and can implement a controlled phase gate via three simultaneous Heisenberg exchange operations. The extra qubits also provide flexibility in the arrangement of the physical qubits. Specifically, all physical qubits of a coherent-preserving qubit lattice can be placed in two spatial dimensions. Such an arrangement allows for universal cluster state computation.

4 pages, 4 figures

References in corpus (17)

• Quantum Computation with Quantum Dots
• Noiseless Quantum Codes
• Electron spin relaxation by nuclei in semiconductor quantum dots
• Universal Quantum Computation with the Exchange Interaction
• Preserving coherence in quantum computation by pairing quantum bits
• Universal quantum computation with spin-1/2 pairs and Heisenberg exchange
• Universal Fault-Tolerant Computation on Decoherence-Free Subspaces
• Double-Occupancy Errors, Adiabaticity, and Entanglement of Spin-Qubits in Quantum Dots
• 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
• Coherence-Preserving Quantum Bits
• Quantum Dot Cluster State Computing with Encoded Qubits
• Three and Four-Body Interactions in Spin-Based Quantum Computers
• Energetic Suppression of Decoherence in Exchange-Only Quantum Computation
• Dispersive Manipulation of Paired Superconducting Qubits
• Few-body spin couplings and their implications for universal quantum computation

Cited by in corpus (10)

• Towards Fault Tolerant Adiabatic Quantum Computation
• Quantum Chaos, Delocalization, and Entanglement in Disordered Heisenberg Models
• Preparation of Decoherence Free Cluster States with Optical Superlattices
• Entanglement Sudden Death as an Indicator of Fidelity in a Four-Qubit Cluster State
• Improving Intrinsic Decoherence in Multi-Quantum-Dot Charge Qubits
• Entanglement Sudden Death in a Quantum Memory
• Singlet-only Always-on Gapless Exchange Qubits with Baseband Control
• Robust preparation and manipulation of protected qubits using time--varying Hamiltonians
• The Spin Density Matrix I: General Theory and Exact Master Equations
• Quantum Gates Between Two Spins in a Triple Dot System with an Empty Dot