A Wavelength-Insensitive, Multispecies Entangling Gate for Group-2 Atomic Ions

Abstract

We propose an optical scheme for generating entanglement between co-trapped identical or dissimilar alkaline earth atomic ions (${}^{40}{\text{Ca}}^{+}$, ${}^{88}{\text{Sr}}^{+}$, ${}^{138}{\text{Ba}}^{+}$, ${}^{226}{\text{Ra}}^{+}$) which exhibits fundamental error rates below $10^{-4}$ and can be implemented with a broad range of laser wavelengths spanning from ultraviolet to infrared. We also discuss straightforward extensions of this technique to include the two lightest Group-2 ions (${\text{Be}}^{+}$, ${\text{Mg}}^{+}$) for multispecies entanglement. The key elements of this wavelength-insensitive geometric phase gate are the use of a ground ($S_{1/2}$) and a metastable ($D_{5/2}$) electronic state as the qubit levels within a ${\sigma }^z{\sigma }^z$ light-shift entangling gate. We present a detailed analysis of the principles and fundamental error sources for this gate scheme which includes photon scattering and spontaneous emission decoherence, calculating two-qubit-gate error rates and durations at fixed laser beam intensity over a large portion of the optical spectrum (300 nm to 2 $\mu \text{m}$) for an assortment of ion pairs. We contrast the advantages and disadvantages of this technique against previous trapped-ion entangling gates and discuss its applications to quantum information processing and simulation with like and multispecies ion crystals.

arXiv comment16 pages, 5 figures

References in corpus (33)

• Experimental issues in coherent quantum-state manipulation of trapped atomic ions
• Quantum computing with trapped ions
• Observation of a Many-Body Dynamical Phase Transition with a 53-Qubit Quantum Simulator
• Engineered 2D Ising interactions on a trapped-ion quantum simulator with hundreds of spins
• Entanglement and quantum computation with ions in thermal motion
• High-fidelity two-qubit quantum logic gates using trapped calcium-43 ions
• High-fidelity quantum logic gates using trapped-ion hyperfine qubits
• Direct observation of dynamical quantum phase transitions in an interacting many-body system
• High-Fidelity Universal Gate Set for ${}^9$Be${}^{+}$ Ion Qubits
• Towards fault-tolerant quantum computing with trapped ions
• Quantum chemistry calculations on a trapped-ion quantum simulator
• Long-lived qubit memory using atomic ions
• High-fidelity readout of trapped-ion qubits
• Integrated multi-wavelength control of an ion qubit
• Integrated optical multi-ion quantum logic
• Quantum Approximate Optimization of the Long-Range Ising Model with a Trapped-Ion Quantum Simulator
• Multi-Element Logic Gates for Trapped-Ion Qubits
• Ion trap quantum gates with amplitude-modulated laser beams
• Coherent Error Suppression in Multi-Qubit Entangling Gates
• Hybrid quantum logic and a test of Bell's inequality using two different atomic isotopes
• Quantum entanglement between an atom and a molecule
• Decoherence due to elastic Rayleigh scattering
• Dipolar quantum logic for freely-rotating trapped molecular ions
• Amplitude sensing below the zero-point fluctuations with a two-dimensional trapped-ion mechanical oscillator
• Heating rate and electrode charging measurements in a scalable, microfabricated, surface-electrode ion trap
• Single-mode optical fiber for high-power, low-loss UV transmission
• Benchmarking a high-fidelity mixed-species entangling gate
• Laser-induced charging of microfabricated ion traps
• Dual-Species, Multi-Qubit Logic Primitives for Ca+/Sr+ Trapped-Ion Crystals
• Dipole-phonon quantum logic with trapped polar molecular ions
• Geometric phase gate on an optical transition for ion trap quantum computation
• A high fidelity light-shift gate for clock-state qubits
• High-fidelity ion-trap quantum computing with hyperfine clock states

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• High-Fidelity Bell-State Preparation with ${}^{40}$Ca${}^{+}$ Optical Qubits
• Noisy intermediate-scale quantum computers
• Native qudit entanglement in a trapped ion quantum processor
• Photon scattering errors during stimulated Raman transitions in trapped-ion qubits
• Synthesizing a ${\hat{\sigma }}_z$ spin-dependent force for optical, metastable, and ground state trapped-ion qubits
• Entanglement between a trapped ion qubit and a 780-nm photon via quantum frequency conversion
• Errors in stimulated-Raman-induced logic gates in ${}^{133}$Ba${}^{+}$
• Transport-enabled entangling gate for trapped ions
• Rapid Exchange Cooling with Trapped Ions
• Entangling gates for trapped-ion quantum computation and quantum simulation
• Comparison of Spontaneous Emission in Trapped Ion Multiqubit Gates at High Magnetic Fields
• Compilation of Entangling Gates for High-Dimensional Quantum Systems
• Demonstration of two-dimensional connectivity for a scalable error-corrected ion-trap quantum processor architecture
• A simplified Mølmer-Sørensen gate for the trapped ion quantum computer
• Improving trapped-ion-qubit memories via code-mediated error-channel balancing
• Exactly-solved model of light-scattering errors in quantum simulations with metastable trapped-ion qubits