Experimental implementation of quantum gates through actuator qubits

Abstract

Universal quantum computation requires the implementation of arbitrary control operations on the quantum register. In most cases, this is achieved by external control fields acting selectively on each qubit to drive single-qubit operations. In combination with a drift Hamiltonian containing interactions between the qubits, this allows the implementation of any required gate operation. Here, we demonstrate an alternative scheme that does not require local control for all qubits: we implement one- and two-qubit gate operations on a set of target qubits indirectly, through a combination of gates on directly controlled actuator qubits with a drift Hamiltonian that couples actuator and target qubits. Experiments are performed on nuclear spins, using radio-frequency pulses as gate operations and magnetic-dipole couplings for the drift Hamiltonian.

References in corpus (8)

• Quantum Computing
• Solid state quantum memory using the 31P nuclear spin
• Liquid State NMR as a Test-bed for Developing Quantum Control Methods
• Universal Control of Nuclear Spins Via Anisotropic Hyperfine Interactions
• An alternative quantum fidelity for mixed states of qudits
• Switched Control of Electron Nuclear Spin Systems
• Experimental protection of quantum gates against decoherence and control errors
• Iterative quantum state transfer along a chain of nuclear spin qubits