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تسجيل مستخدم جديدBatch Optimization of Frequency-Modulated Pulse for Robust Two-qubit Gates in Ion Chains
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Two-qubit gates in trapped ion quantum computers are generated by applying spin-dependent forces that temporarily entangle the internal state of the ion with its motion. Laser pulses are carefully designed to generate a maximally entangling gate between the ions while minimizing any residual entanglement between the motion and the ion. The quality of the gates suffers when actual experimental parameters differ from the ideal case. Here we improve the robustness of frequency-modulated M{o}lmer-S{o}rensen gates to motional mode frequency offsets by optimizing average performance over a range of systematic errors using batch optimization. We then compare this method to frequency modulated gates optimized for ideal parameters that include an analytic robustness condition. Numerical simulations show good performance up to 12 ions and the method is experimentally demonstrated on a two-ion chain.
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In an ion trap quantum computer, collective motional modes are used to entangle two or more qubits in order to execute multi-qubit logical gates. Any residual entanglement between the internal and motional states of the ions results in loss of fideli
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We study a class of entangling gates for trapped atomic ions and demonstrate the use of numeric optimization techniques to create a wide range of fast, error-robust gate constructions. Our approach introduces a framework for numeric optimization usin
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