Wavelength-insensitive, multispecies entangling gate for group-2 atomic ions

Sawyer, Brian C.; Brown, Kenton R.

doi:10.1103/physreva.103.022427

Cited by 23 publications

(17 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have recently proposed a variant of the LS gate scheme where the qubit levels are separated by an optical frequency and the gate laser wavelength is far detuned from any atomic resonance [17]. Some advantages of this optical transition dipole force (OTDF) gate include: compatibility with dynamical decoupling pulse sequences [15,18], a broad range of feasible entangling gate laser wavelengths (including visible wavelengths), two-qubit photon scattering error below 10 −4 in some wavelength regimes, and straightforward extension to co-trapped disparate species group-2 ions.…”

mentioning

confidence: 99%

“…As in Ref. [17], we choose |↓ = S 1/2 (m j = 1/2) and |↑ = D 5/2 (m j = 3/2) as the qubit states (m j here is the projection of total angular momentum along the quantization axis). This optical qubit transition frequency is linearly sensitive to magnetic field variations, which thereby form a potentially large source of decoherence in our experiments, but the incorporation of a Hahn spin echo into the OTDF gate mitigates this deficiency [15,23].…”

mentioning

confidence: 99%

“…1(a)] to create a moving optical lattice which drives the ions with a spin-dependent optical-dipole force (ODF). We choose to generate entanglement with a wavelength of 532 nm, where high-power single-longitudinal-mode lasers are readily available, and where photon scattering errors are nearly minimized [17]. The wavevector difference between the beams is oriented along the z axis, so that only the motional modes along this direction are driven.…”

mentioning

confidence: 99%

“…The ODF beams are created from a single seed laser whose intensity is controlled via an acousto-opticmodulator (AOM). Using this AOM, we ramp the intensities of both beams in tandem with sine-squared tapers at the beginning and end of each ODF pulse; such adiabatic ramping is important to suppress sensitivity to the absolute phase of the optical lattice [10,17]. Each of the ODF beams passes in turn through an additional AOM, so that its frequency and phase can be controlled independently and its intensity can be stabilized via monitoring and feedback.…”

mentioning

confidence: 99%

See 3 more Smart Citations

High-Fidelity Bell-State Preparation with $^{40}$Ca$^+$ Optical Qubits

Clark,

Tinkey,

Sawyer

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Entanglement generation in trapped-ion systems has relied thus far on two distinct but related geometric phase gate techniques: Mølmer-Sørensen and light-shift gates. We recently proposed a variant of the light-shift scheme where the qubit levels are separated by an optical frequency [B. C. Sawyer and K. R. Brown, Phys. Rev. A 103, 022427 ( 2021)]. Here we report an experimental demonstration of this entangling gate using a pair of 40 Ca + ions in a cryogenic surface-electrode ion trap and a commercial, high-power, 532 nm Nd:YAG laser. Generating a Bell state in 35 µs, we directly measure an infidelity of 6(3) × 10 −4 without subtraction of experimental errors. The 532 nm gate laser wavelength suppresses intrinsic photon scattering error to ∼ 1 × 10 −5 . This result establishes our scheme as competitive with previously demonstrated entangling gates.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

High-Fidelity Bell-State Preparation with $^{40}$Ca$^+$ Optical Qubits

Clark,

Tinkey,

Sawyer

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…The transport gate technique demonstrated here could be extended to longer ion strings with different motional modes and ion species with appropriate changes in beam geometry. In particular, the scheme is amenable to σ z σ z interactions such as the optical-transition dipole force gate [25,26] where the Stark shift effects could be eliminated entirely with an echo pulse.…”

mentioning

confidence: 99%

Transport-enabled entangling gate for trapped ions

Tinkey,

Clark,

Sawyer

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

We implement a two-qubit entangling Mølmer-Sørensen interaction by transporting two cotrapped 40 Ca + ions through a stationary, bichromatic optical beam within a surface-electrode Paul trap. We describe a procedure for achieving a constant Doppler shift during the transport which uses fine temporal adjustment of the moving confinement potential. The fixed interaction duration of the ions transported through the laser beam as well as the dynamically changing ac Stark shift require alterations to the calibration procedures used for a stationary gate. We use the interaction to produce Bell states with fidelities commensurate to those of stationary gates performed in the same system. This result establishes the feasibility of actively incorporating ion transport into quantum information entangling operations.

show abstract

Noisy intermediate-scale quantum computers

Cheng

Deng

et al. 2023

Front. Phys.

View full text Add to dashboard Cite

Quantum computers have made extraordinary progress over the past decade, and significant milestones have been achieved along the path of pursuing universal fault-tolerant quantum computers. Quantum advantage, the tipping point heralding the quantum era, has been accomplished along with several waves of breakthroughs. Quantum hardware has become more integrated and architectural compared to its toddler days. The controlling precision of various physical systems is pushed beyond the fault-tolerant threshold. Meanwhile, quantum computation research has established a new norm by embracing industrialization and commercialization. The joint power of governments, private investors, and tech companies has significantly shaped a new vibrant environment that accelerates the development of this field, now at the beginning of the noisy intermediate-scale quantum era. Here, we first discuss the progress achieved in the field of quantum computation by reviewing the most important algorithms and advances in the most promising technical routes, and then summarizing the next-stage challenges. Furthermore, we illustrate our confidence that solid foundations have been built for the fault-tolerant quantum computer and our optimism that the emergence of quantum killer applications essential for human society shall happen in the future.

show abstract

Wavelength-insensitive, multispecies entangling gate for group-2 atomic ions

Cited by 23 publications

References 39 publications

High-Fidelity Bell-State Preparation with $^{40}$Ca$^+$ Optical Qubits

High-Fidelity Bell-State Preparation with $^{40}$Ca$^+$ Optical Qubits

Transport-enabled entangling gate for trapped ions

Noisy intermediate-scale quantum computers

Contact Info

Product

Resources

About