Breaking the entangling gate speed limit for trapped-ion qubits using a phase-stable standing wave
(2023)
Verifiable blind quantum computing with trapped ions and single photons
(2023)
Robust quantum memory in a trapped-ion quantum network node
Physical Review Letters American Physical Society 130 (2023) 090803
Abstract:
We integrate a long-lived memory qubit into a mixed-species trapped-ion quantum network node. Ion-photon entanglement first generated with a network qubit in 88Sr+ is transferred to 43Ca+ with 0.977(7) fidelity, and mapped to a robust memory qubit. We then entangle the network qubit with another photon, which does not affect the memory qubit. We perform quantum state tomography to show that the fidelity of ion-photon entanglement decays ∼ 70 times slower on the memory qubit. Dynamical decoupling further extends the storage time; we measure an ion-photon entanglement fidelity of 0.81(4) after 10 s.Synthesizing a Sigma circumflex accent z spin-dependent force for optical, metastable, and ground-state trapped-ion qubits
Physical Review A American Physical Society 107:2 (2023) 22617
Abstract:
A single bichromatic field near resonant to a qubit transition is typically used for σx or σy Mølmer-Sørensen-type interactions in trapped-ion systems. Using this field configuration, it is also possible to synthesize a σz spin-dependent force by merely adjusting the beat-note frequency. Here, we expand on previous work and present a comprehensive theoretical and experimental investigation of this scheme with a laser near resonant to a quadrupole transition in Sr+88. Further, we characterize its robustness to optical phase and qubit frequency offsets, and demonstrate its versatility by entangling optical, metastable, and ground-state qubits.A quantum network of two entangled optical atomic clocks
SPIE, the international society for optics and photonics (2023) 1