2013/12/31 by Xin Wang, Lev S. Bishop, Edwin Barnes +2 · 1 citation
Computer Science · Physics and Astronomy · #Composite material #Composite number #Excited state #Materials science #Optoelectronics #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum gate #Quantum mechanics #Qubit #Singlet state #Spin (aerodynamics) #cond-mat.mes-hall #quant-ph
paper · pdf · doi:10.1103/physreva.89.022310
published as Phys. Rev. A 89, 022310 (2014) · 22+ pages, 15 figures
arxiv created 2014/02/11 · openalex publication_date 2014/02/11 · arxiv updated 2014/02/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present a comprehensive theoretical treatment of supcode, a method for generating dynamically corrected quantum gate operations, which are immune to random noise in the environment, by using carefully designed sequences of soft pulses. supcode enables dynamical error suppression even when the control field is constrained to be positive and uniaxial, making it particularly suited to counteracting the effects of noise in systems subject to these constraints such as singlet-triplet qubits. We describe and explain in detail how to generate supcode pulse sequences for arbitrary single-qubit gates and provide several explicit examples of sequences that implement commonly used gates, including the single-qubit Clifford gates. We develop sequences for noise-resistant two-qubit gates for two exchange-coupled singlet-triplet qubits by cascading robust single-qubit gates, leading to a 35% reduction in gate time compared to previous works. This cascade approach can be scaled up to produce gates for an arbitrary-length spin qubit array and is thus relevant to scalable quantum computing architectures. To more accurately describe real spin qubit experiments, we show how to design sequences that incorporate additional features and practical constraints such as sample-specific charge noise models and finite pulse rise times. We provide a detailed analysis based on randomized benchmarking to show how supcode gates perform under realistic 1/f^\ensuremathα noise and find a strong dependence of gate fidelity on the exponent \ensuremathα, with best performance for \ensuremathα>1. Our supcode sequences can therefore be used to implement robust universal quantum computation while accommodating the fundamental constraints and experimental realities of singlet-triplet qubits.