175 citations · 1.6k across the 65 of their papers we have counts for
61 papers · 1 filter
Instantaneous Quantum Polynomial-Time Sampling and Verifiable Quantum Advantage: Stabilizer Scheme and Classical Security
Michael J. Bremner, Bin Cheng, Zhengfeng Ji
Sampling problems demonstrating beyond classical computing power with noisy intermediate scale quantum devices have been experimentally realized. In those realizations, however, ou…
Logarithmic-Regret Quantum Learning Algorithms for Zero-Sum Games
Minbo Gao, Zhengfeng Ji, Tongyang Li +1
We propose the first online quantum algorithm for solving zero-sum games with regret under the game setting. Moreover, our quantum algorithm computes an $\varepsi…
Classical and Quantum Iterative Optimization Algorithms Based on Matrix Legendre-Bregman Projections
Zhengfeng Ji
We consider Legendre-Bregman projections defined on the Hermitian matrix space and design iterative optimization algorithms based on them. A general duality theorem is established…
Quantum Parameterized Complexity
Michael J. Bremner, Zhengfeng Ji, Ryan L. Mann +3
Parameterized complexity theory was developed in the 1990s to enrich the complexity-theoretic analysis of problems that depend on a range of parameters. In this paper we establish…
Quantum soundness of testing tensor codes
Zhengfeng Ji, Anand Natarajan, Thomas Vidick +2
A locally testable code is an error-correcting code that admits very efficient probabilistic tests of membership. Tensor codes provide a simple family of combinatorial construction…
Symbolic Verification of Quantum Circuits
Mingsheng Ying, Zhengfeng Ji
This short note proposes a symbolic approach for representing and reasoning about quantum circuits using complex, vector or matrix-valued Boolean expressions. A major benefit of th…
Quantum soundness of the classical low individual degree test
Zhengfeng Ji, Anand Natarajan, Thomas Vidick +2
Low degree tests play an important role in classical complexity theory, serving as basic ingredients in foundational results such as [BFL91] and the…
Quantum proof systems for iterated exponential time, and beyond
Joseph Fitzsimons, Zhengfeng Ji, Thomas Vidick +1
We show that any language in nondeterministic time , where the number of iterated exponentials is an arbitrary function , can be decided by a mult…
A three-player coherent state embezzlement game
Zhengfeng Ji, Debbie Leung, Thomas Vidick
We introduce a three-player nonlocal game, with a finite number of classical questions and answers, such that the optimal success probability of in the game can only be achieve…
Pseudorandom States, Non-Cloning Theorems and Quantum Money
Zhengfeng Ji, Yi-Kai Liu, Fang Song
We propose the concept of pseudorandom states and study their constructions, properties, and applications. Under the assumption that quantum-secure one-way functions exist, we pres…
A Separability-Entanglement Classifier via Machine Learning
Sirui Lu, Shilin Huang, Keren Li +7
The problem of determining whether a given quantum state is entangled lies at the heart of quantum information processing, which is known to be an NP-hard problem in general. Despi…
Compression of Quantum Multi-Prover Interactive Proofs
Zhengfeng Ji
We present a protocol that transforms any quantum multi-prover interactive proof into a nonlocal game in which questions consist of logarithmic number of bits and answers of consta…
Joint product numerical range and geometry of reduced density matrices
Jianxin Chen, Cheng Guo, Zhengfeng Ji +4
The reduced density matrices of a many-body quantum system form a convex set, whose three-dimensional projection is convex in . The boundary of ma…
Physical origins of ruled surfaces on the reduced density matrices geometry
Ji-Yao Chen, Zhengfeng Ji, Zheng-Xin Liu +4
The reduced density matrices (RDMs) of many-body quantum states form a convex set. The boundary of low dimensional projections of this convex set may exhibit nontrivial geometry su…
Quantum State and Process Tomography via Adaptive Measurements
Hengyan Wang, Wenqiang Zheng, Nengkun Yu +9
We investigate quantum state tomography (QST) for pure states and quantum process tomography (QPT) for unitary channels via measurements. For a quantum system with a …
Dichotomy of entanglement depth for symmetric states
Ji-Yao Chen, Zhengfeng Ji, Nengkun Yu +1
Entanglement depth characterizes the minimal number of particles in a system that are mutually entangled. For symmetric states, we show that there is a dichotomy for entanglement d…
Zero-knowledge proof systems for QMA
Anne Broadbent, Zhengfeng Ji, Fang Song +1
Prior work has established that all problems in NP admit classical zero-knowledge proof systems, and under reasonable hardness assumptions for quantum computations, these proof sys…
Quantum state tomography via reduced density matrices
Tao Xin, Dawei Lu, Joel Klassen +7
Quantum state tomography via local measurements is an efficient tool for characterizing quantum states. However it requires that the original global state be uniquely determined (U…
Quantum Capacities for Entanglement Networks
Shawn X Cui, Zhengfeng Ji, Nengkun Yu +1
We discuss quantum capacities for two types of entanglement networks: for the quantum repeater network with free classical communication, and for the te…
Pure State Tomography with Pauli Measurements
Xian Ma, Tyler Jackson, Hui Zhou +10
We examine the problem of finding the minimum number of Pauli measurements needed to uniquely determine an arbitrary -qubit pure state among all quantum states. We show that onl…
Tomography is necessary for universal entanglement detection with single-copy observables
Dawei Lu, Tao Xin, Nengkun Yu +7
Entanglement, one of the central mysteries of quantum mechanics, plays an essential role in numerous applications of quantum information theory. A natural question of both theoreti…
Detecting Consistency of Overlapping Quantum Marginals by Separability
Jianxin Chen, Zhengfeng Ji, Nengkun Yu +1
The quantum marginal problem asks whether a set of given density matrices are consistent, i.e., whether they can be the reduced density matrices of a global quantum state. Not many…
Geometry of reduced density matrices for symmetry-protected topological phases
Ji-Yao Chen, Zhengfeng Ji, Zheng-Xin Liu +2
In this paper, we study the geometry of reduced density matrices for states with symmetry-protected topological (SPT) order. We observe ruled surface structures on the boundary of…
Sample-optimal tomography of quantum states
Jeongwan Haah, Aram W. Harrow, Zhengfeng Ji +2
It is a fundamental problem to decide how many copies of an unknown mixed quantum state are necessary and sufficient to determine the state. Previously, it was known only that esti…