Universal quantum interfaces

Abstract

To observe or control a quantum system, one must interact with it via an interface. This letter exhibits simple universal quantum interfaces--quantum input/output ports consisting of a single two-state system or quantum bit that interacts with the system to be observed or controlled. It is shown that under very general conditions the ability to observe and control the quantum bit on its own implies the ability to observe and control the system itself. The interface can also be used as a quantum communication channel, and multiple quantum systems can be connected by interfaces to become an efficient universal quantum computer. Experimental realizations are proposed, and implications for controllability, observability, and quantum information processing are explored.

4 pages, 3 figures, RevTeX

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Cited by in corpus (36)

• Perfect state transfer in quantum spin networks
• A Review of Perfect State Transfer and its Application as a Constructive Tool
• Full control by locally induced relaxation
• Scalable quantum computation via local control of only two qubits
• Local controllability of quantum networks
• Universal observable detecting all two-qubit entanglement and determinant based separability tests
• Robust Entanglement in Anti-ferromagnetic Heisenberg Chains by Single-spin Optimal Control
• Engineering Quantum States of a Nano-Resonator via a Simple Auxiliary System
• Control by quantum dynamics on graphs
• Quantum logic gates for superconducting resonator qudits
• Symmetry & Controllability for Spin Networks with a Single-Node Control
• Quantum thermodynamics with local control
• Computation on Spin Chains with Limited Access
• Single-bit Feedback and Quantum Dynamical Decoupling
• Noise resilient quantum interface based on QND interaction
• Controlling qubit arrays with anisotropic XXZ Heisenberg interaction by acting on a single qubit
• The Computational Power of Symmetric Hamiltonians
• Universal scheme for indirect quantum control
• Probabilistic Quantum Control Via Indirect Measurement
• Complete Quantum-State Tomography with a Local Random Field
• General construction of noiseless networks detecting entanglement with help of linear maps
• Interfacing with Hamiltonian Dynamics
• Operational Entanglement Detection Based on $\Lambda$-Moments
• Quantum State Preparation by Controlled Dissipation in Finite Time: From Classical to Quantum Controllers
• Drawing together control landscape and tomography principles
• Efficiently Controllable Graphs
• The NV center as a quantum actuator: time-optimal control of nuclear spins
• Probing untouchable environment as a resource for quantum computing
• Elliptical orbits in the Bloch sphere
• Scalable quantum computation based on quantum actuated nuclear-spin decoherence-free qubits
• Quantum computation with noisy operations
• Quantum Games and Programmable Quantum Systems
• Programmable Quantum State Transfer
• Algebra and Hilbert space structures induced by quantum probes
• Quantum Defragmentation Algorithm
• How much is a quantum controller controlled by the controlled system?