Scalable quantum logic using engineered spin in diamond

• Applicant: Professor Dr. Fedor Jelezko
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2010 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 164540649

Ultimately a quantum information device is likely to be a solid state component. It is the aim of this work package to pave the way towards such a unit based on spins in diamond. Based on existing 2 qubits devices for the project period we aim at extending the number of qubits to 3-5 with the prospect of scaling towards larger units. Scaling spin based systems in diamond will employ two different types of interaction. On the one hand spin photon entanglement with subsequent photon interference on a beam splitter allows for resource friendly scaling but is limited to low temperature operation. On the other hand direct coupling between electrons spins is an altemative which is rebuts enough to allow room temperature operation with sufficient fidelity. It is this latter way which should be chosen in this work package. Success requires reliable control over the environment as well as optimized read out and nanopositioning technology. To this end the workpackage addresses the following objectives:1. To design, fabricate and characterize quantum registers with spin qubits in NV centres in diamond by implantation of electron spins in high purity isotopically engineered diamond materials. 2. To establish optical read out technique allowing addressing spin qubits with nanometer resolution. 3. To develop and implement protocols and algorithms that make maximal use of dipolar coupled electron spins. 4. Develop and realize protocols allowing robust deterministic entanglement in a quantum register consisting of a few electron or nuclear spins coupled via magnetic interactions 5. Develop quantum interface for transfer of quantum information between single spin in diamond and photons 6. To apply the full power of quantum control techniques on qubits and their environment to maximize coherence times. 7. Develop projective, high-fidelity readout (quantum non-demolition measurement) of single spin

• DFG Programme: Research Units
• Subproject of: FOR 1482: Quantum Computing in Isotopically Engineered Diamond
• Major Instrumentation: Fast Switching Microwave Single Generator ; microwave amplifier
• Instrumentation Group: 5310 Interferenzapparaturen, Zweistrahl-Interferometer ; 6040 Frequenz-Umformer (statisch) und Hochfrequenzgeneratoren
• Participating Person: Professor Dr. Jörg Wrachtrup