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Related papers: Time optimal quantum control of two-qubit systems

200 papers

We study time-minimum optimal control for a class of quantum two-dimensional dissipative systems whose dynamics are governed by the Lindblad equation and where control inputs acts only in the Hamiltonian. The dynamics of the control system…

Optimization and Control · Mathematics 2019-04-24 William Clark , Anthony Bloch , Leonardo Colombo , Patrick Rooney

We experimentally study the time-optimal construction of arbitrary single-qubit rotations under a single strong driving field of finite amplitude. Using radiation-dressed states of nitrogen vacancy centers in diamond, we realize a…

Quantum Physics · Physics 2014-07-02 Chen Avinadav , Ran Fischer , Paz London , David Gershoni

For the time optimal control on an invariant system on SU(2), with two independent controls and a bound on the norm of the control, the extremals of the maximum principle are explicit functions of time and the resulting differential…

Quantum Physics · Physics 2014-07-29 Francesca Albertini , Domenico D'Alessandro

We employ optimal control theory to design optimized quantum gates for solid-state qubits subject to decoherence. At the example of a gate-controlled semiconductor quantum dot molecule we demonstrate that decoherence due to phonon couplings…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Ulrich Hohenester

Quantum computation with quantum gates induced by geometric phases is regarded as a promising strategy in fault tolerant quantum computation, due to its robustness against operational noises. However, because of the parametric restriction…

We introduce a novel algorithm for the task of coherently controlling a quantum mechanical system to implement any chosen unitary dynamics. It performs faster than existing state of the art methods by one to three orders of magnitude…

Quantum Physics · Physics 2015-06-04 Pierre de Fouquieres

Optical techniques have been employed to coherently control the quantum transport through nanojunctions. Conventional works on optical control of quantum transport usually applied a tailored electrical pulses to perform specific tasks. In…

Mesoscale and Nanoscale Physics · Physics 2015-10-13 Yu Zhang

Methods of optimal control are applied to a model system of interacting two-level particles (e.g., spin-half atomic nuclei or electrons or two-level atoms) to produce high-fidelity quantum gates while simultaneously negating the detrimental…

We perform optimal-control-theory calculations to determine the minimum number of two-qubit CNOT gates needed to perform quantum state preparation and unitary operator synthesis for few-qubit systems. By considering all possible gate…

Quantum Physics · Physics 2022-08-24 Sahel Ashhab , Naoki Yamamoto , Fumiki Yoshihara , Kouichi Semba

We analytically determine the minimal time and the optimal control laws required for the realization, up to an assigned fidelity and with a fixed energy available, of entangling quantum gates ($\mathrm{CNOT}$) between indirectly coupled…

Quantum Physics · Physics 2014-12-01 A. Carlini , T. Koike

We develop a Hamiltonian switching ansatz for bipartite control that is inspired by the Quantum Approximate Optimization Algorithm (QAOA), to mitigate environmental noise on qubits. We illustrate the approach with application to the…

Quantum Physics · Physics 2024-03-20 Zhibo Yang , Robert L. Kosut , K. Birgitta Whaley

In this dissertation I analyze Hamiltonian control of $d$-dimensional quantum systems as realized in alkali atomic spins. Alkali atoms provide an ideal platform for studies of quantum control due to the extreme precision with which the…

Quantum Physics · Physics 2009-06-29 Seth Merkel

This paper is concerned with the linear quadratic optimal control of discrete-time time-varying system with terminal state constraint. The main contribution is to propose a Q-learning algorithm for the optimal controller when the…

Optimization and Control · Mathematics 2023-07-20 Juanjuan Xu , Jingmei Liu , Zhaorong Zhang , Wei Wang

We investigate simultaneous estimation of multi-parameter quantum estimation with time-dependent Hamiltonians. We analytically obtain the maximal quantum Fisher information matrix for two-parameter in time-dependent three-level systems. The…

Quantum Physics · Physics 2021-09-06 Dong Xie , Chunling Xu

We propose nearly-optimal control strategies for changing states of a quantum system. We argue that quantum control optimization can be studied analytically within some protocol families that depend on a small set of parameters for…

Quantum Physics · Physics 2017-09-13 Chen Sun , Avadh Saxena , Nikolai A. Sinitsyn

Based on a parametrization of pure quantum states we explicitly construct a sequence of (at most) $4N-5$ local time-continuous waveform controls to achieve a specified state transition for $N$-level quantum systems when sufficient controls…

Quantum Physics · Physics 2012-02-17 Ming Zhang , Jia-Hua Wei , Weiwei Zhou , Hong-Yi Dai , Zairong Xi , S. G. Schirmer

In order to demonstrate non-trivial quantum computations experimentally, such as the synthesis of arbitrary entangled states, it will be useful to understand how to decompose a desired quantum computation into the shortest possible sequence…

Quantum Physics · Physics 2009-11-10 Farrokh Vatan , Colin Williams

In this article we analyze the optimal control strategy for rotating a monitored qubit from an initial pure state to an orthogonal state in minimum time. This strategy is described for two different cost functions of interest which do not…

Optimization and Control · Mathematics 2012-11-27 Srinivas Sridharan , Masahiro Yanagisawa , Joshua Combes

We demonstrate, numerically, the possibility of manipulating the spin states of molecular nanomagnets with shaped microwave pulses designed with quantum optimal control theory techniques. The state-to-state or full gate transformations can…

Quantum Physics · Physics 2021-12-01 Alberto Castro , Adrian Garcia Carrizo , David Zueco , Fernando Luis

Exchange-coupled singlet-triplet spin qubits in two gate-defined double quantum dots are considered theoretically. Using charge density operators to describe the double-dot orbital states, we calculate the Coulomb couplings between the…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Guy Ramon