DyPP: Dynamic Parameter Prediction to Accelerate Convergence of Variational Quantum Algorithms

TL;DR

DyPP introduces a dynamic parameter prediction method that significantly accelerates the convergence of variational quantum algorithms, reducing computational costs and improving accuracy across multiple quantum tasks.

Contribution

This paper presents DyPP, a novel approach with NaP and AdaP techniques, to predict parameter updates, achieving faster convergence and better results in VQAs compared to standard methods.

Findings

DyPP achieves approximately 2.25x speedup in training.

DyPP improves accuracy by up to 2.3%.

DyPP reduces the number of shots needed by up to 3.3x.

Abstract

The exponential run time of quantum simulators on classical machines and long queue times and high costs of real quantum devices present significant challenges in the efficient optimization of Variational Quantum Algorithms (VQAs) like Variational Quantum Eigensolver (VQE), Quantum Approximate Optimization Algorithm (QAOA) and Quantum Neural Networks (QNNs). To address these limitations, we propose a new approach, DyPP (Dynamic Parameter Prediction), which accelerates the convergence of VQAs by exploiting regular trends in the parameter weights to update parameters. We introduce two techniques for optimal prediction performance namely, Naive Prediction (NaP) and Adaptive Prediction (AdaP). Through extensive experimentation and training of multiple QNN models on various datasets, we demonstrate that DyPP offers a speedup of approximately $2.25\times$ compared to standard training methods, while also providing improved accuracy (up to $2.3\%$ higher) and loss (up to $6.1\%$ lower) with low storage and computational overheads. We also evaluate DyPP's effectiveness in VQE for molecular ground-state energy estimation and in QAOA for graph MaxCut. Our results show that on average, DyPP leads to speedup of up to $3.1\times$ for VQE and $2.91\times$ for QAOA, compared to traditional optimization techniques, while using up to $3.3\times$ lesser shots (i.e., repeated circuit executions). Even under hardware noise, DyPP outperforms existing optimization techniques, delivering upto $3.33\times$ speedup and $2.5\times$ fewer shots, thereby enhancing efficiency of VQAs.