English
Related papers

Related papers: Shallow shadows: Expectation estimation using low-…

200 papers

Accurately estimating expectation values of quantum observables with as few measurements as possible is crucial to many quantum computing applications. We introduce a framework that covers many of existing measurement strategies and…

Classical shadow tomography is a powerful randomized measurement protocol for predicting many properties of a quantum state with few measurements. Two classical shadow protocols have been extensively studied in the literature: the…

Quantum Physics · Physics 2023-06-07 Ahmed A. Akhtar , Hong-Ye Hu , Yi-Zhuang You

Predicting properties of large-scale quantum systems is crucial for the development of quantum science and technology. Shadow estimation is an efficient method for this task based on randomized measurements, where many-qubit random Clifford…

Quantum Physics · Physics 2024-04-24 Qingyue Zhang , Qing Liu , You Zhou

Properties of quantum systems can be estimated using classical shadows, which implement measurements based on random ensembles of unitaries. Originally derived for global Clifford unitaries and products of single-qubit Clifford gates,…

Quantum Physics · Physics 2023-09-25 Mirko Arienzo , Markus Heinrich , Ingo Roth , Martin Kliesch

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 study classical shadows protocols based on randomized measurements in $n$-qubit entangled bases, generalizing the random Pauli measurement protocol ($n = 1$). We show that entangled measurements ($n\geq 2$) enable nontrivial and…

Quantum Physics · Physics 2024-03-27 Matteo Ippoliti

We present a robust shadow estimation protocol for wide classes of low-depth measurement circuits that mitigates noise as long as the effective measurement map including noise is locally unitarily invariant. This is in practice an excellent…

Quantum Physics · Physics 2025-03-26 Renato M. S. Farias , Raghavendra D. Peddinti , Ingo Roth , Leandro Aolita

Extracting information efficiently from quantum systems is a major component of quantum information processing tasks. Randomized measurements, or classical shadows, enable predicting many properties of arbitrary quantum states using few…

Shadow estimation is a recent protocol that allows estimating exponentially many expectation values of a quantum state from ``classical shadows'', obtained by applying random quantum circuits and computational basis measurements. In this…

Quantum Physics · Physics 2023-12-27 Jonas Helsen , Michael Walter

We propose a resource-efficient shadow-tomography scheme using equatorial-stabilizer measurements generated from subsets of Clifford unitaries. For $n$-qubit systems, equatorial-stabilizer-based shadow-tomography schemes can estimate $M$…

Quantum Physics · Physics 2025-08-01 Guedong Park , Yong Siah Teo , Hyunseok Jeong

Quantum shadow tomography based on the classical shadow representation provides an efficient way to estimate properties of an unknown quantum state without performing a full quantum state tomography. In scenarios where estimating the…

Quantum Physics · Physics 2026-03-13 Aniket Sengupta , Arijit Chatterjee , G. J. Sreejith , T. S. Mahesh

A constant number of random Clifford measurements allows the classical shadow protocol to perform direct fidelity estimation (DFE) with high precision. However, estimating properties of an unknown quantum state is expected to be more…

Quantum Physics · Physics 2025-09-17 Hyunho Cha , Jungwoo Lee

Given copies of a quantum state $\rho$, a shadow tomography protocol aims to learn all expectation values from a fixed set of observables, to within a given precision $\epsilon$. We say that a shadow tomography protocol is triply efficient…

Quantum Physics · Physics 2025-03-28 Robbie King , David Gosset , Robin Kothari , Ryan Babbush

Efficiently learning expectation values of unknown quantum states via classical shadows has become an important primitive in both theoretical and experimental aspects of quantum computation. Typically, classical shadow protocols involve…

Quantum Physics · Physics 2026-05-08 Rebecca Chang , Maureen Krumtünger , Martin Larocca , Maxwell West

Classical shadows are a powerful method for learning many properties of quantum states in a sample-efficient manner, by making use of randomized measurements. Here we study the sample complexity of learning the expectation value of Pauli…

Quantum Physics · Physics 2023-06-13 Matteo Ippoliti , Yaodong Li , Tibor Rakovszky , Vedika Khemani

Classical shadow tomography (CST) involves obtaining enough classical descriptions of an unknown state via quantum measurements to predict the outcome of a set of quantum observables. CST has numerous applications, particularly in…

Quantum Physics · Physics 2025-05-22 Zahra Honjani , Mohsen Heidari

The classical shadow estimation protocol is a noise-resilient and sample-efficient quantum algorithm for learning the properties of quantum systems. Its performance depends on the choice of a unitary ensemble, which must be chosen by a user…

Quantum Physics · Physics 2024-01-10 Kaifeng Bu , Dax Enshan Koh , Roy J. Garcia , Arthur Jaffe

We develop a classical shadow tomography protocol utilizing the randomized measurement scheme based on hybrid quantum circuits, which consist of layers of two-qubit random unitary gates mixed with single-qubit random projective…

Quantum Physics · Physics 2023-09-26 Ahmed A. Akhtar , Hong-Ye Hu , Yi-Zhuang You

Measuring global quantum properties-such as the fidelity to complex multipartite states-is both an essential and experimentally challenging task. Classical shadow estimation offers favorable sample complexity, but typically relies on…

Quantum Physics · Physics 2026-02-11 Qingyue Zhang , Dayue Qin , Zhou You , Feng Xu , Jens Eisert , You Zhou

In quantum information theory, the accurate estimation of observables is pivotal for quantum information processing, playing a crucial role in compute and communication protocols. This work introduces a novel technique for estimating such…

Quantum Physics · Physics 2024-09-17 Andrea Caprotti , Joshua Morris , Borivoje Dakić
‹ Prev 1 2 3 10 Next ›