154 citations · 715 across the 17 of their papers we have counts for
17 papers
Near-optimal covariant quantum error-correcting codes from random unitaries with symmetries
Linghang Kong, Zi-Wen Liu
Quantum error correction and symmetries play central roles in quantum information science and physics. It is known that quantum error-correcting codes that obey (are covariant with…
Quantum error correction meets continuous symmetries: fundamental trade-offs and case studies
Zi-Wen Liu, Sisi Zhou
We systematically study the fundamental competition between quantum error correction (QEC) and continuous symmetries, two key notions in quantum information and physics, in a quant…
Global Heisenberg scaling in noisy and practical phase estimation
Masahito Hayashi, Zi-Wen Liu, Haidong Yuan
Heisenberg scaling characterizes the ultimate precision of parameter estimation enabled by quantum mechanics, which represents an important quantum advantage of both theoretical an…
Learning quantum data with the quantum Earth Mover's distance
Bobak Toussi Kiani, Giacomo De Palma, Milad Marvian +2
Quantifying how far the output of a learning algorithm is from its target is an essential task in machine learning. However, in quantum settings, the loss landscapes of commonly us…
Many-body quantum magic
Zi-Wen Liu, Andreas Winter
Magic (non-stabilizerness) is a necessary but "expensive" kind of "fuel" to drive universal fault-tolerant quantum computation. To properly study and characterize the origin of qua…
Symmetry-protected sign problem and magic in quantum phases of matter
Tyler D. Ellison, Kohtaro Kato, Zi-Wen Liu +1
We introduce the concepts of a symmetry-protected sign problem and symmetry-protected magic to study the complexity of symmetry-protected topological (SPT) phases of matter. In par…
No-go theorems for quantum resource purification II: new approach and channel theory
Kun Fang, Zi-Wen Liu
It has been recently shown that there exist universal fundamental limits to the accuracy and efficiency of the transformation from noisy resource states to pure ones (e.g.,~distill…
New perspectives on covariant quantum error correction
Sisi Zhou, Zi-Wen Liu, Liang Jiang
Covariant codes are quantum codes such that a symmetry transformation on the logical system could be realized by a symmetry transformation on the physical system, usually with limi…
A Separation of Out-of-time-ordered Correlation and Entanglement
Aram W. Harrow, Linghang Kong, Zi-Wen Liu +2
The out-of-time-ordered correlation (OTOC) and entanglement are two physically motivated and widely used probes of the "scrambling" of quantum information, a phenomenon that has dr…
Generalized Entanglement Entropies of Quantum Designs
Zi-Wen Liu, Seth Lloyd, Elton Yechao Zhu +1
The entanglement properties of random quantum states or dynamics are important to the study of a broad spectrum of disciplines of physics, ranging from quantum information to high…
Diagonal quantum discord
Zi-Wen Liu, Ryuji Takagi, Seth Lloyd
Quantum discord measures quantum correlation by comparing the quantum mutual information with the maximal amount of mutual information accessible to a quantum measurement. This pap…
Maximizing free energy gain
Artemy Kolchinsky, Iman Marvian, Can Gokler +6
Maximizing the amount of work harvested from an environment is important for a wide variety of biological and technological processes, from energy-harvesting processes such as phot…
Entanglement, quantum randomness, and complexity beyond scrambling
Zi-Wen Liu, Seth Lloyd, Elton Yechao Zhu +1
Scrambling is a process by which the state of a quantum system is effectively randomized due to the global entanglement that "hides" initially localized quantum information. In thi…
Resource Destroying Maps
Zi-Wen Liu, Xueyuan Hu, Seth Lloyd
Resource theory is a widely-applicable framework for analyzing the physical resources required for given tasks, such as computation, communication, and energy extraction. In this p…
No energy transport without discord
Seth Lloyd, Zi-Wen Liu, Stefano Pirandola +4
We show that without quantum correlations, energy cannot flow. The result follows from a simple theorem that shows that systems whose dynamics do not generate quantum discord are e…
Doubly infinite separation of quantum information and communication
Zi-Wen Liu, Christopher Perry, Yechao Zhu +2
We prove the existence of (one-way) communication tasks with a subconstant versus superconstant asymptotic gap, which we call "doubly infinite," between their quantum information a…
Optical Analogue of Quantum Spin Hall Effect in a Two-Dimensional Gyrotropic Photonic Crystal
Cheng He, Xiao-Chen Sun, Xiao-ping Liu +4
We propose an optical counterpart of the quantum spin Hall (QSH) effect in a two-dimensional photonic crystal composed of a gyrotropic medium exhibiting both gyroelectric and gyrom…