Entanglement of a nuclear spin qubit register in silicon photonics

Abstract

Color centers provide an optical interface to quantum registers based on electron and nuclear spin qubits in solids. The T center in silicon is an emerging spin-photon interface that combines telecom O-band optical transitions and an electron spin in a scalable photonics platform. In this work, we demonstrate the initialization, coherent control, and state readout of a three-qubit register based on the electron spin of a T center coupled to a hydrogen and a silicon nuclear spin. The spin register exhibits spin echo coherence times of $0.41(2)$~ms for the electron spin, $112(12)$~ms for the hydrogen nuclear spin, and $67(7)$~ms for the silicon nuclear spin. We use nuclear-nuclear two-qubit gates to generate entanglement between the two nuclear spins with a fidelity of $F=0.77(3)$ and a coherence time of $T_2^{\ast }=2.60(8)$~ms. Our results show that a T center in silicon photonics can realize a multi-qubit register with an optical interface for quantum communication.

Nat. Nanotechnol. (2025)

References in corpus (8)

• Universal dynamical decoupling of a single solid-state spin from a spin bath
• Detection and control of individual nuclear spins using a weakly coupled electron spin
• Entanglement of Nanophotonic Quantum Memory Nodes in a Telecom Network
• A silicon-integrated telecom photon-spin interface
• Cavity-coupled telecom atomic source in silicon
• Mapping a 50-spin-qubit network through correlated sensing
• Cavity enhanced emission from a silicon T center
• Tomography of entangling two-qubit logic operations in exchange-coupled donor electron spin qubits

Cited by in corpus (2)

• Silicon T centre hyperfine structure and memory protection schemes
• Spin-photon Qubits for Scalable Quantum Network