English
Related papers

Related papers: Measurement-Induced Criticality is Tomographically…

200 papers

In this paper, we present a Hamiltonian identification method for a closed quantum system whose time trace observables are measured with colored measurement noise. The dynamics of the quantum system are described by a Liouville equation…

Systems and Control · Computer Science 2020-10-20 Lingyu Tan , Daoyi Dong , Dewei Li , Shibei Xue

Extracting information from quantum systems is crucial in quantum physics and information processing. Methods based on randomized measurements, like shadow estimation, show advantages in effectively achieving such tasks. However, randomized…

Quantum Physics · Physics 2024-09-10 Zhou You , Qing Liu , You Zhou

We present a quantum circuit model which emulates the interface growth of the classical raise-and-peel model. Our model consists of Clifford unitary gates interspersed with projective measurements, applied according to prescribed feedback…

Quantum Physics · Physics 2024-08-08 Eliot Heinrich , Xiao Chen

We propose a tomographic protocol for estimating any $ k $-body reduced density matrix ($ k $-RDM) of an $ n $-mode fermionic state, a ubiquitous step in near-term quantum algorithms for simulating many-body physics, chemistry, and…

Quantum Physics · Physics 2022-10-04 Andrew Zhao , Nicholas C. Rubin , Akimasa Miyake

A central challenge in quantum computing is to identify more computational problems for which utilization of quantum resources can offer significant speedup. Here, we propose a hybrid quantum-classical scheme to tackle the quantum optimal…

Quantum Physics · Physics 2017-04-19 Jun Li , Xiaodong Yang , Xinhua Peng , Chang-Pu Sun

Quantum process tomography is a critical capability for building quantum computers, enabling quantum networks, and understanding quantum sensors. Like quantum state tomography, the process tomography of an arbitrary quantum channel requires…

Quantum Physics · Physics 2023-05-26 Jonathan Kunjummen , Minh C. Tran , Daniel Carney , Jacob M. Taylor

Quantum computers are now on the brink of outperforming their classical counterparts. One way to demonstrate the advantage of quantum computation is through quantum random sampling performed on quantum computing devices. However, existing…

We consider the problem of estimating quantum observables on a collection of qubits, given as a linear combination of Pauli operators, with shallow quantum circuits consisting of single-qubit rotations. We introduce estimators based on…

Quantum Physics · Physics 2022-08-08 Stefan Hillmich , Charles Hadfield , Rudy Raymond , Antonio Mezzacapo , Robert Wille

We propose a quantum tomography scheme for pure qudit systems which adopts random base measurements and generative learning methods, along with a built-in fidelity estimation approach to assess the reliability of the tomographic states. We…

Quantum Physics · Physics 2020-03-25 Jun Wang , Zhao-Yu Han , Song-Bo Wang , Zeyang Li , Liang-Zhu Mu , Heng Fan , Lei Wang

The temporal evolution of a quantum system can be characterized by quantum process tomography, a complex task that consumes a number of physical resources scaling exponentially with the number of subsystems. An alternative approach to the…

We describe a new shadow tomography algorithm that uses $n=\Theta(\sqrt{m}\log m/\epsilon^2)$ samples, for $m$ measurements and additive error $\epsilon$, which is independent of the dimension of the quantum state being learned. This stands…

Quantum Physics · Physics 2024-11-05 Pulkit Sinha

Quantum state tomography is a key process in most quantum experiments. In this work, we employ quantum machine learning for state tomography. Given an unknown quantum state, it can be learned by maximizing the fidelity between the output of…

We study the role of continuous measurement in the quantum to classical transition for a system with coupled internal (spin) and external (motional) degrees of freedom. Even when the measured motional degree of freedom can be treated…

Quantum sensing harnesses the unique properties of quantum systems to enable precision measurements of physical quantities such as time, magnetic and electric fields, acceleration, and gravitational gradients well beyond the limits of…

Quantum Physics · Physics 2025-07-23 Ivana Nikoloska , Ruud Van Sloun , Osvaldo Simeone

Variational quantum metrology represents a powerful tool for optimizing generic estimation strategies, combining the principles of variational optimization with the techniques of quantum metrology. Such optimization procedures result…

This paper presents a hybrid classical-quantum program for density estimation and supervised classification. The program is implemented as a quantum circuit in a high-dimensional quantum computer simulator. We show that the proposed quantum…

We investigate entanglement phase transitions from volume-law to area-law entanglement in a quantum many-body state under continuous position measurement on the basis of the quantum trajectory approach. We find the signatures of the…

Statistical Mechanics · Physics 2021-02-15 Yohei Fuji , Yuto Ashida

Von Neumann projections are the main operations by which information can be extracted from the quantum to the classical realm. They are however static processes that do not adapt to the states they measure. Advances in the field of adaptive…

Quantum Physics · Physics 2015-10-28 Amine Laghaout , Ulrik L. Andersen

Quantum computers are poised to radically outperform their classical counterparts by manipulating coherent quantum systems. A realistic quantum computer will experience errors due to the environment and imperfect control. When these errors…

Quantum Physics · Physics 2016-11-21 Joel J. Wallman , Joseph Emerson

We describe how randomized benchmarking can be used to reconstruct the unital part of any trace-preserving quantum map, which in turn is sufficient for the full characterization of any unitary evolution, or more generally, any unital…

Quantum Physics · Physics 2016-04-12 Shelby Kimmel , Marcus P. da Silva , Colm A. Ryan , Blake R. Johnson , Thomas Ohki