English
Related papers

Related papers: Learning k-qubit Quantum Operators via Pauli Decom…

200 papers

Characterizing quantum processes is essential for unlocking the potential of quantum devices. However, standard quantum process tomography is resource-intensive and becomes infeasible on large-scale systems. Despite alternative approaches…

Quantum Physics · Physics 2026-02-24 Hao Zhan , Zongbo Bao , Zekun Ye , Qianyi Wang , Minghao Mi , Penghui Yao , Lijian Zhang

With the aim of establishing a framework to efficiently perform the practical application of quantum chemistry simulation on near-term quantum devices, we envision a hybrid quantum--classical framework for leveraging problem decomposition…

Efficiently learning expectation values of a quantum state using classical shadow tomography has become a fundamental task in quantum information theory. In a classical shadows protocol, one measures a state in a chosen basis W after it has…

Quantum Physics · Physics 2025-06-04 Maxwell West , Antonio Anna Mele , Martin Larocca , M. Cerezo

We introduce $k$-local quasi-quantum states: a superset of the regular quantum states, defined by relaxing the positivity constraint. We show that a $k$-local quasi-quantum state on $n$ qubits can be 1-1 mapped to a distribution of…

Quantum Physics · Physics 2025-01-27 Itai Arad , Miklos Santha

We prove that the linearity and positivity of quantum mechanics impose general restrictions on quantum purification, unveiling a new fundamental limitation of quantum information processing. In particular, no quantum operation can transform…

Quantum Physics · Physics 2025-09-26 Zhenhuan Liu , Zhenyu Du , Zhenyu Cai , Zi-Wen Liu

Quantum machine learning, as an extension of classical machine learning that harnesses quantum mechanics, facilitates effiient learning from data encoded in quantum states. Training a quantum neural network typically demands a substantial…

Quantum Physics · Physics 2026-02-17 Yongcheng Ding , Yue Ban , Mikel Sanz , José D. Martín-Guerrero , Xi Chen

This short study reformulates the statistical Bayesian learning problem using a quantum mechanics framework. Density operators representing ensembles of pure states of sample wave functions are used in place probability densities. We show…

Statistics Theory · Mathematics 2023-01-18 Yann Berquin

Measurement-based quantum computing uses measurement patterns on predefined quantum resource states to execute quantum logic. Quantum simulation offers an important use case on near-term devices. However, pattern optimization depends on the…

Quantum Physics · Physics 2026-05-13 V. W. Scarola

The first quantum technologies to solve computational problems that are beyond the capabilities of classical computers are likely to be devices that exploit characteristics inherent to a particular physical system, to tackle a bespoke…

We study the problem of learning the Hamiltonian of a quantum many-body system given samples from its Gibbs (thermal) state. The classical analog of this problem, known as learning graphical models or Boltzmann machines, is a well-studied…

Quantum Physics · Physics 2021-05-26 Anurag Anshu , Srinivasan Arunachalam , Tomotaka Kuwahara , Mehdi Soleimanifar

Importance sampling based on quasi-probability decomposition is the backbone of many widely used techniques, such as error mitigation, circuit knitting, and, more generally, virtual quantum resource distillation, as it allows one to…

Quantum Physics · Physics 2026-03-27 Shinnosuke Onishi , Oliver Hahn , Ryuji Takagi

This paper investigates symmetric composite binary quantum hypothesis testing (QHT), where the goal is to determine which of two uncertainty sets contains an unknown quantum state. While asymptotic error exponents for this problem are…

Quantum Physics · Physics 2026-04-13 Jacob Paul Simpson , Efstratios Palias , Sharu Theresa Jose

Detecting multipartite entanglement in many qubit systems is measurement-intensive, motivating protocols that estimate only selected observables with provable efficiency. In this work we use the classical shadow protocol to study the sample…

Quantum Physics · Physics 2026-01-06 Ziran Zhang

Quantum Boltzmann machines (QBMs) are machine-learning models for both classical and quantum data. We give an operational definition of QBM learning in terms of the difference in expectation values between the model and target, taking into…

Quantum Physics · Physics 2025-02-13 Luuk Coopmans , Marcello Benedetti

We study the sample complexity of the prototypical tasks quantum purity estimation and quantum inner product estimation. In purity estimation, we are to estimate $tr(\rho^2)$ of an unknown quantum state $\rho$ to additive error $\epsilon$.…

Quantum Physics · Physics 2024-10-17 Weiyuan Gong , Jonas Haferkamp , Qi Ye , Zhihan Zhang

Estimating expectation values on near-term quantum computers often requires a prohibitively large number of measurements. One widely-used strategy to mitigate this problem has been to partition an operator's Pauli terms into sets of…

As quantum computers approach the fault tolerance threshold, diagnosing and characterizing the noise on large scale quantum devices is increasingly important. One of the most important classes of noise channels is the class of Pauli…

Quantum Physics · Physics 2021-02-17 Robin Harper , Wenjun Yu , Steven T. Flammia

Although classical computing has excelled in a wide range of applications, there remain problems that push the limits of its capabilities, especially in fields like cryptography, optimization, and materials science. Quantum computing…

Software Engineering · Computer Science 2025-01-14 Neilson Carlos Leite Ramalho , Erico Augusto da Silva , Higor Amario de Souza , Marcos Lordello Chaim

Quantum software testing is important for reliable quantum software engineering. Despite recent advances, existing quantum software testing approaches rely on simple test inputs and statistical oracles, costly program specifications, and…

Software Engineering · Computer Science 2026-02-13 Asmar Muqeet , Shaukat Ali , Paolo Arcaini

Simulating the dynamics of complex quantum systems is a central application of quantum devices. Here, we propose leveraging the power of measurements to simulate short-time quantum dynamics of physically prepared quantum states in classical…

Quantum Physics · Physics 2025-07-02 Paul K. Faehrmann , Jens Eisert , Maria Kieferova , Richard Kueng