English
Related papers

Related papers: Quantum Control of a Single Qubit

200 papers

Quantum metrology seeks to leverage the richness of quantum systems for making better measurements than are possible using only classical resources in order to gain a ``quantum advantage''. Quantum metrology schemes must also be resilient…

Acquiring information about an unknown qubit in a superposition of two states is essential in any computation process. Quantum measurement, or sharp measurement, is usually used to read the information contents of that unknown qubit system.…

Quantum Physics · Physics 2017-04-26 Ahmed Younes

We consider a general quantum system interacting with a bath and derive a master equation in the Lindblad form describing the evolution of the whole quantum system subjected to a measurement-based direct quantum feedback control (MDFC). As…

Quantum Physics · Physics 2015-06-17 Yan Yan , Jian Zou , Bao-Ming Xu , Jun-Gang Li , Bin Shao

Quantum measurement is a fundamental cornerstone of experimental quantum computations. The main issues in current quantum measurement strategies are the high number of measurement rounds to determine a global optimal measurement output and…

Quantum Physics · Physics 2019-05-02 Laszlo Gyongyosi , Sandor Imre

To exploit a given physical system for quantum information processing, it is critical to understand the different types of noise affecting quantum control. Distinguishing coherent and incoherent errors is extremely useful as they can be…

Recent progress in quantum physics has made it possible to perform experiments in which individual quantum systems are monitored and manipulated in real time. The advent of such new technical capabilities provides strong motivation for the…

Quantum Physics · Physics 2016-11-18 Andrew Doherty , John Doyle , Hideo Mabuchi , Kurt Jacobs , Salman Habib

An incoherent control scheme for state control of locally controllable quantum systems is proposed. This scheme includes three steps: (1) amplitude amplification of the initial state by a suitable unitary transformation, (2) projective…

Quantum Physics · Physics 2008-10-22 Daoyi Dong , Chenbin Zhang , Herschel Rabitz , Alexander Pechen , Tzyh-Jong Tarn

Quantum probing is the art of exploiting simple quantum systems interacting with a complex environment to extract precise information about some environmental parameters, e.g. the temperature of the environment or its spectral density. Here…

Quantum Physics · Physics 2020-08-26 Dario Tamascelli , Claudia Benedetti , Heinz-Peter Breuer , Matteo G. A. Paris

In this article, we explore the possibility of achieving noise suppression for finite-dimensional quantum systems through coherent feedback. For a quantum plant which is expected to evolve according to a target trajectory, noise effect…

Quantum Physics · Physics 2024-09-10 Shikun Zhang , Guofeng Zhang

Novel concepts, perspectives and challenges in measuring and controlling an open quantum system via sequential schemes are shown. We discuss how similar protocols, relying both on repeated quantum measurements and dynamical decoupling…

Quantum Physics · Physics 2019-06-26 Stefano Gherardini , Andrea Smirne , Matthias M. Müller , Filippo Caruso

In circuit-based quantum computing, the available gate set typically consists of single-qubit gates acting on each individual qubit and at least one entangling gate between pairs of qubits. In certain physical architectures, however, some…

Quantum Physics · Physics 2022-09-23 M. Pechal , G. Salis , M. Ganzhorn , D. J. Egger , M. Werninghaus , S. Filipp

Most of the research done on quantum error correction studies an error model in which each qubit is affected by noise, independently of the other qubits. In this paper we study a different noise model -- one in which the noise may be…

Quantum Physics · Physics 2009-09-09 Avraham Ben-Aroya , Amnon Ta-Shma

Quantum sensing exploits fundamental features of quantum system to achieve highly efficient measurement of physical quantities. Here, we propose a strategy to realize a single-qubit pseudo-Hermitian sensor from a dilated two-qubit Hermitian…

Quantum Physics · Physics 2020-01-22 Yaoming Chu , Yu Liu , Haibin Liu , Jianming Cai

A central challenge for implementing quantum computing in the solid state is decoupling the qubits from the intrinsic noise of the material. We investigate the implementation of quantum gates for a paradigmatic, non-Markovian model: A…

Quantum Physics · Physics 2010-04-22 P. Rebentrost , I. Serban , T. Schulte-Herbrueggen , F. K. Wilhelm

A major goal of developing high-precision control of many-body quantum systems is to realise their potential as quantum computers. Probably the most significant obstacle in this direction is the problem of "decoherence": the extreme…

The scope of this work is to provide a self-contained introduction to a selection of basic theoretical aspects in the modeling and control of quantum mechanical systems, as well as a brief survey on the main approaches to control synthesis.…

Quantum Physics · Physics 2012-10-29 Claudio Altafini , Francesco Ticozzi

In this paper we consider feedback control algorithms for the rapid purification of a bipartite state consisting of two qubits, when the observer has access to only one of the qubits. We show 1) that the algorithm that maximizes the average…

Quantum Physics · Physics 2009-11-13 Charles D. Hill , J. F. Ralph

Quantum state tomography (QST) represents an essential tool for the characterization, verification, and validation (QCVV) of quantum processors. Only for a few idealized scenarios, there are analytic results for the optimal measurement set…

Quantum Physics · Physics 2022-12-27 Violeta N. Ivanova-Rohling , Niklas Rohling , Guido Burkard

Coherent feedback is a non-measurement based, hence a back-action free, method of control for quantum systems. A typical application of this control scheme is squeezing enhancement, a purely non-classical effect in quantum optics. In this…

Quantum Physics · Physics 2016-11-17 Sanae Iida , Mitsuyoshi Yukawa , Hidehiro Yonezawa , Naoki Yamamoto , Akira Furusawa

Quantum control allows a wide range of quantum operations employed in molecular physics, nuclear magnetic resonance and quantum information processing. Thanks to the existing microelectronics industry, semiconducting qubits, where quantum…

Quantum Physics · Physics 2024-12-05 Jia-Ao Peng , Chu-Dan Qiu , Wen-Long Ma , Jun-Wei Luo