Robust quantum-network memory based on spin qubits in isotopically engineered diamond

Quantum networks can enable quantum communication and modular quantum computation. A powerful approach is to use multi-qubit nodes that provide quantum memory and computational power. Nuclear spins associated with defects in diamond are promising qubits for this role. However, dephasing during optical entanglement distribution hinders scaling...

Entanglement of Spin-Pair Qubits with Intrinsic Dephasing Times Exceeding a Minute

Understanding and protecting the coherence of individual quantum systems is a central challenge in quantum science and technology. Over the past decades, a rich variety of methods to extend coherence have been developed. A complementary approach is to look for naturally occurring systems that are inherently protected against decoherence. Here...

On the creation, coherence and entanglement of multi-defect quantum registers in diamond

Due to its long spin coherence and coherent spin-photon interface the nitrogen vacancy (NV) center in diamond has emerged as a promising platform for quantum science and technology, including quantum networks, quantum computing and quantum sensing. In recent years larger quantum systems have been demonstrated by using optical entanglement links...

Entanglement of dark electron-nuclear spin defects in diamond

A promising approach for multi-qubit quantum registers is to use optically addressable spins to control multiple dark electron-spin defects in the environment. While recent experiments have observed signatures of coherent interactions with such dark spins, it is an open challenge to realize the individual control required for quantum...

Optical coherence of diamond nitrogen-vacancy centers formed by ion implantation and annealing

The advancement of quantum optical science and technology with solid-state emitters such as nitrogen-vacancy (NV) centers in diamond critically relies on the coherence of the emitters' optical transitions. A widely employed strategy to create NV centers at precisely controlled locations is nitrogen ion implantation followed by a high...

A Ten-Qubit Solid-State Spin Register with Quantum Memory up to One Minute

Spins associated with single defects in solids provide promising qubits for quantum-information processing and quantum networks. Recent experiments have demonstrated long coherence times, high-fidelity operations, and long-range entanglement. However, control has so far been limited to a few qubits, with entangled states of three spins...