The role of master clock stability in scalable quantum information processing

Abstract

Experimentalists seeking to improve the coherent lifetimes of quantum bits have generally focused on mitigating decoherence mechanisms through, for example, improvements to qubit designs and materials, and system isolation from environmental perturbations. In the case of the phase degree of freedom in a quantum superposition, however, the coherence that must be preserved is not solely internal to the qubit, but rather necessarily includes that of the qubit relative to the "master clock" (e.g. a local oscillator) that governs its control system. In this manuscript we articulate the impact of instabilities in the master clock on qubit phase coherence, and provide tools to calculate the contributions to qubit error arising from these processes. We first connect standard oscillator phase-noise metrics to their corresponding qubit dephasing spectral densities. We then use representative lab-grade and performance-grade oscillator specifications to calculate operational fidelity bounds on trapped-ion and superconducting qubits with relatively slow and fast operation times. We discuss the relevance of these bounds for quantum error correction in contemporary experiments and future large-scale quantum information systems, and discuss potential means to improve master clock stability.

Related manuscripts available from http://www.physics.usyd.edu.au/~mbiercuk/Publications.html

References in corpus (18)

• Dynamical decoupling and noise spectroscopy with a superconducting flux qubit
• Elucidating Reaction Mechanisms on Quantum Computers
• Optimized Dynamical Decoupling in a Model Quantum Memory
• High-fidelity preparation, gates, memory and readout of a trapped-ion quantum bit
• Superconducting qubit in waveguide cavity with coherence time approaching 0.1ms
• Fault-Tolerant Quantum Dynamical Decoupling
• Manipulation and Detection of a Trapped Yb+ Ion Hyperfine Qubit
• Dynamically Error-Corrected Gates for Universal Quantum Computation
• Hybrid quantum-classical approach to correlated materials
• Optimal Dynamical Decoherence Control of a Qubit
• Exact Results on Dynamical Decoupling by $\pi$-Pulses in Quantum Information Processes
• Restoring Coherence Lost to a Slow Interacting Mesoscopic Bath
• Experimental noise filtering by quantum control
• Life after charge noise: recent results with transmon qubits
• Dynamical Quantum Error Correction of Unitary Operations with Bounded Controls
• The effect of noise correlations on randomized benchmarking
• Experimental bath engineering for quantitative studies of quantum control
• Ultra-low vibration pulse-tube cryocooler stabilized cryogenic sapphire oscillator with 10^-16 fractional frequency stability

Cited by in corpus (3)

• Dynamical decoupling sequences for multi-qubit dephasing suppression and long-time quantum memory
• Control and Readout Software in Superconducting Quantum Computing
• Scalable Self-Adaptive Synchronous Triggering System in Superconducting Quantum Computing