126 citations · 892 across the 24 of their papers we have counts for
25 papers
The classical capacity of generalized amplitude-damping channels and its strong-converse exponent
Kun Fang
The classical capacity of a quantum channel generally requires regularization because input codewords may be entangled across channel uses. We remove this regularization for genera…
Quantum NETwork: from theory to practice
Kun Fang, Jingtian Zhao, Xiufan Li +2
The quantum internet is envisioned as the ultimate stage of the quantum revolution, which surpasses its classical counterpart in various aspects, such as the efficiency of data tra…
Finite-Key Analysis of Quantum Key Distribution with Characterized Devices Using Entropy Accumulation
Ian George, Jie Lin, Thomas van Himbeeck +2
The Entropy Accumulation Theorem (EAT) was introduced to significantly improve the finite-size rates for device-independent quantum information processing tasks such as device-inde…
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…
Finite Block Length Analysis on Quantum Coherence Distillation and Incoherent Randomness Extraction
Masahito Hayashi, Kun Fang, Kun Wang
We give the first systematic study on the second order asymptotics of the operational task of coherence distillation with and without assistance. In the unassisted setting, we intr…
A chain rule for the quantum relative entropy
Kun Fang, Omar Fawzi, Renato Renner +1
The chain rule for the classical relative entropy ensures that the relative entropy between probability distributions on multipartite systems can be decomposed into a sum of relati…
Geometric Rényi Divergence and its Applications in Quantum Channel Capacities
Kun Fang, Hamza Fawzi
We present a systematic study of the geometric Rényi divergence (GRD), also known as the maximal Rényi divergence, from the point of view of quantum information theory. We show tha…
No-Go Theorems for Quantum Resource Purification
Kun Fang, Zi-Wen Liu
The manipulation of quantum "resources" such as entanglement, coherence and magic states lies at the heart of quantum science and technology, empowering potential advantages over c…
The Complementary Information Principle of Quantum Mechanics
Yunlong Xiao, Kun Fang, Gilad Gour
The uncertainty principle bounds the uncertainties about incompatible measurements, clearly setting quantum theory apart from the classical world. Its mathematical formulation via…
The sum-of-squares hierarchy on the sphere, and applications in quantum information theory
Kun Fang, Hamza Fawzi
We consider the problem of maximizing a homogeneous polynomial on the unit sphere and its hierarchy of Sum-of-Squares (SOS) relaxations. Exploiting the polynomial kernel technique,…
One-shot entanglement distillation beyond local operations and classical communication
Bartosz Regula, Kun Fang, Xin Wang +1
We study the task of entanglement distillation in the one-shot setting under different classes of quantum operations which extend the set of local operations and classical communic…
Quantum Channel Simulation and the Channel's Smooth Max-Information
Kun Fang, Xin Wang, Marco Tomamichel +1
We study the general framework of quantum channel simulation, that is, the ability of a quantum channel to simulate another one using different classes of codes. First, we show tha…
Quantum Advantages in Hypercube Game
Xiaoyu He, Kun Fang, Xiaoming Sun +1
We introduce a novel generalization of the Clauser-Horne-Shimony-Holt (CHSH) game to a multiplayer setting, i.e., Hypercube game, where all players are required to assign value…
Using and reusing coherence to realize quantum processes
María García Díaz, Kun Fang, Xin Wang +4
Coherent superposition is a key feature of quantum mechanics that underlies the advantage of quantum technologies over their classical counterparts. Recently, coherence has been re…
Probabilistic distillation of quantum coherence
Kun Fang, Xin Wang, Ludovico Lami +2
The ability to distill quantum coherence is pivotal for optimizing the performance of quantum technologies; however, such a task cannot always be accomplished with certainty. Here…
One-shot coherence distillation
Bartosz Regula, Kun Fang, Xin Wang +1
We characterize the distillation of quantum coherence in the one-shot setting, that is, the conversion of general quantum states into maximally coherent states under different clas…
On converse bounds for classical communication over quantum channels
Xin Wang, Kun Fang, Marco Tomamichel
We explore several new converse bounds for classical communication over quantum channels in both the one-shot and asymptotic regimes. First, we show that the Matthews-Wehner meta-c…
Semidefinite programming converse bounds for quantum communication
Xin Wang, Kun Fang, Runyao Duan
We derive several efficiently computable converse bounds for quantum communication over quantum channels in both the one-shot and asymptotic regime. First, we derive one-shot semid…
Non-asymptotic entanglement distillation
Kun Fang, Xin Wang, Marco Tomamichel +1
Entanglement distillation, an essential quantum information processing task, refers to the conversion from multiple copies of noisy entangled states to a smaller number of highly e…
Approximate broadcasting of quantum correlations
Wei Xie, Kun Fang, Xin Wang +1
Broadcasting quantum and classical information is a basic task in quantum information processing, and is also a useful model in the study of quantum correlations including quantum…
Phase separation instabilities and pairing modulations in
Kun Fang, G. W. Fernando, A. V. Balatsky +2
There is growing evidence that the unconventional spatial inhomogeneities in the doped high-Tc superconductors are accompanied by the pairing of electrons, subsequent quantum phase…
Quantum critical points and phase separation instabilities in Hubbard nanoclusters
A. N. Kocharian, Kun Fang, G. W. Fernando
Spontaneous phase separation instabilities with the formation of various types of charge and spin pairing (pseudo)gaps in Hubbard model including the {\it next nearest neighb…
Local electronic nematicity in the one-band Hubbard model
Kun Fang, G. W. Fernando, A. K. Kocharian
Nematicity is a well known property of liquid crystals and has been recently discussed in the context of strongly interacting electrons. An electronic nematic phase has been seen b…
Pairing enhancement in Betts lattices with next nearest neighbor couplings: Exact results
Kun Fang, Gayanath Fernando, Armen Kocharian
Electron instabilities in the Hubbard model with the next nearest neighbor coupling are calculated by exact diagonalization in finite, two-dimensional Betts cells (lattices). A via…