arXiv subjects

Zong-Liang Li

Publications and source records attributed to Zong-Liang Li.

4 recordsLinked to original sources

arXiv2026

Non-Hermitian Dirac Vortex: Minimal Theory for Topological-Cavity Surface-Emitting Laser

We construct a non-Hermitian Dirac-vortex model that combines a complex-mass winding with an infinite-imaginary-potential boundary, extending the Jackiw-Rossi and neutrino-billiard models to the dissipative regime. Moreover, this model serves as a minimal theory for the recently proposed topological-cavity surfaceemitting laser (TCSEL): the imaginary mass encodes vertical radiation loss and the absorbing boundary defines the active region. We derive closed-form expressions for the modal frequencies, thresholds, and tunable vectorbeam polarizations, which are validated experimentally. Our work provides a rare example in which an analytical non-Hermitian topological theory captures the essential physics for engineering practical optoelectronic devices.

physics.optics↗

arXiv2026

TensorCircuit-NG: A Universal, Composable, and Scalable Platform for Quantum Computing and Quantum Simulation

We present TensorCircuit-NG, a next-generation quantum software platform designed to bridge the gap between quantum physics, artificial intelligence, and high-performance computing. Moving beyond the scope of traditional circuit simulators, TensorCircuit-NG establishes a unified, tensor-native programming paradigm where quantum circuits, tensor networks, and neural networks fuse into a single, end-to-end differentiable computational graph. Built upon industry-standard machine learning backends (JAX, TensorFlow, PyTorch), the framework introduces comprehensive capabilities for approximate circuit simulation, analog dynamics, fermion Gaussian states, qudit systems, and scalable noise modeling. To tackle the exponential complexity of deep quantum circuits, TensorCircuit-NG implements advanced distributed computing strategies, including automated data parallelism and model-parallel tensor network slicing. We validate these capabilities on GPU clusters, demonstrating a near-linear speedup in distributed variational quantum algorithms. TensorCircuit-NG enables flagship applications, including end-to-end QML for CIFAR-100 computer vision, efficient pipelines from quantum states to neural networks via classical shadows, and differentiable optimization of tensor network states for many-body physics.

quant-ph↗

arXiv2026

The Dual Role of Low-Weight Pauli Propagation: A Flawed Simulator but a Powerful Initializer for Variational Quantum Algorithms

Variational quantum algorithms are often hindered by rugged optimization landscapes. In this Letter, we investigate the low-weight Pauli propagation (LWPP) algorithm and find that it serves as an unreliable energy estimator for variational circuits. However, we reveal a counterintuitive insight: the Pauli-weight truncation acts as a spectral filter, effectively smoothing out high-frequency local minima while preserving the global basin of attraction in the landscape. We identify this mechanism as landscape alignment, where the approximate landscape becomes a superior navigator compared to the rugged exact landscape. Benchmarks across diverse spin models and molecular systems demonstrate that LWPP-initialized optimization yields order-of-magnitude improvements in accuracy, often finding solutions inaccessible to direct exact optimization. This work reframes LWPP from a flawed simulator into a vital pre-optimizer that serves not only as a cheap classical substitute but also as an essential tool for addressing quantum optimization challenges.

quant-ph↗

arXiv2023

Modulating magnetic and electronic properties of lead-apatite Pb$_{10}$(PO$_4$)$_6$O via different transition metal doping

Based on the first-principles electronic structure calculations, we investigate the magnetic and electronic properties of transition-metal-doped Pb$_{10}$(PO$_4$)$_6$O with the Pb atom substituted by various transition metals. The $3d$ orbitals of the doped transition metals are distributed near the Fermi energy and exhibit strong spin-polarization, resulting in the local magnetic moment. With the doped metal varying from V, Cr, Mn, Fe, Co, Ni, Cu, to Zn, the moment changes gradually from 3.0, 4.0, 5.0, 4.0, 3.0, 2.0, 1.0, to 0 $μ_B$, while the electronic structure is modulated progressively due to the continuous change of total charge. Moreover, the flat bands near the Fermi energy are also found in the V, Cr, and Fe-doped lead-apatite, similar to the Cu-doped system. Our work not only provides the critical comparative information for investigating the Cu-doped lead-apatite, but also suggest a category of diluted magnetic semiconductor.

cond-mat.mtrl-sci↗