Quantum information with nv centers in diamond and superconducting qubits
Patrice Bertet (Quantronics Group, CEA Saclay, France)

Infos Complémentaires

Salle E244 - 24, rue Lhomond - 13h30

Jeudi 6 décembre

Quantum information requires quantum-mechanical systems with both long coherence
times and that can be easily coupled together in order to perform quantum
logic operations. NV centers are color centers in a diamond crystal, and consist of
a substitutional Nitrogen atom sitting next to a Vacancy. They carry an electronic
spin that has a long coherence time even at room temperature, which is naturally
trapped in the diamond matrix, and can be easily readout with laser light ; as such
they are interesting candidates for quantum information. However it is utterly difficult
to entangle two separate NV centers. This motivates to investigate “hybrid quantum
circuit” architectures in which NV centers are coupled to auxiliary systems, possibly
mediating their interaction. Superconducting quantum circuits based on Josephson
junctions would be ideal for that purpose.

In this talk I will briefly review the progress of quantum information processing with
NV centers. I will then describe the experiments made in our group where we realize
a hybrid quantum circuit with NV centers and superconducting circuits. As a proofof-
principle experiment, we stored a single microwave photon emitted by a superrconducting
qubit in an ensemble of 1011 NV centers, and retrieved it partially into
the qubit with a fidelity of about 10%. I will discuss the potential of these systems for
realizing a quantum memory with long storage time.

Salle E244 - 24, rue Lhomond - 13h30