Quantum control methods for robust entanglement of trapped ions

Abstract

A major obstacle in the way of practical quantum computing is achieving scalable and robust high-fidelity entangling gates. To this end, quantum control has become an essential tool, as it can make the entangling interaction resilient to sources of noise. Nevertheless, it may be difficult to identify an appropriate quantum control technique for a particular need given the breadth of work pertaining to robust entanglement. To this end, we attempt to consolidate the literature by providing a non-exhaustive summary and critical analysis. The quantum control methods are separated into two categories: schemes which extend the robustness to (i) spin or (ii) motional decoherence. We choose to focus on extensions of the ${\sigma }_x\otimes {\sigma }_x$ Molmer-Sorensen interaction using microwaves and a static magnetic field gradient. Nevertheless, some of the techniques discussed here can be relevant to other trapped ion architectures or physical qubit implementations. Finally, we experimentally realize a proof-of-concept interaction with simultaneous robustness to spin and motional decoherence by combining several quantum control methods presented in this manuscript.

29 pages, 23 figures

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Cited by in corpus (6)

• Realizing quantum gates with optically-addressable ${}^{171}$Yb${}^{+}$ ion qudits
• Engineering dynamically decoupled quantum simulations with trapped ions
• Designing Filter Functions of Frequency-Modulated Pulses for High-Fidelity Two-Qubit Gates in Ion Chains
• Robust two-qubit trapped ions gates using spin-dependent squeezing
• Quadrupole transitions and quantum gates protected by continuous dynamic decoupling
• Robust Oscillator-Mediated Phase Gates Driven by Low-Intensity Pulses