activity
20242026
collaborators

20 papers

quant-ph2026

From Barren Plateaus to SPSA Optimization in Variational Quantum Eigensolvers

Zhen Qin

The barren plateau (BP) phenomenon poses a fundamental challenge to the trainability of variational quantum eigensolvers (VQEs) by causing exponentially vanishing gradients as the…

quant-ph2026

A Unified Framework for Sample Complexity of Structured Quantum State Tomography under Noisy Observations

Zhen Qin

Quantum state tomography (QST) has attracted considerable attention due to its fundamental role in quantum information processing. In this paper, we develop a unified theoretical f…

quant-ph2026

Structured Factorization Approaches for Quantum State Tomography

Zhen Qin, Joseph M. Lukens, Brian T. Kirby +1

Since the complexity of quantum state tomography (QST) scales exponentially with system size, exploiting priors such as low-rankness, tensor-network structures, and neural-network…

cs.LG2026

Structured Adaptive Tensor Prediction for Streaming Data

Zhen Qin, Yang Chen

Matrix-valued time series arise in a wide range of applications, such as spatio-temporal data from medical imaging and geophysics. Existing methods are mainly designed for static s…

quant-ph2026

Geometric Analysis of Variational Quantum Eigensolver

Zhen Qin

The Variational Quantum Eigensolver (VQE) is a fundamental algorithm in quantum computing, yet a coherent geometric characterization of VQE remains missing due to fragmented analys…

quant-ph2026

Statistical and Algorithmic Foundations of Probing Quantum Systems with Compressive Measurements: A Review

Zhen Qin, Michael B. Wakin, Zhihui Zhu

Quantum state tomography (QST) is a fundamental task in quantum information science that aims to reconstruct unknown quantum states from measurement data. However, the exponential…