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Related papers: Quantum Optimal Control for Pure-State Preparation…

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Quantum state preparation is a fundamental task in quantum computing and quantum information processing. With the rapid advancement of quantum technologies, efficient quantum state preparation has become increasingly important. This paper…

Quantum Physics · Physics 2025-07-22 Xin Hong , Chenjian Li , Aochu Dai , Sanjiang Li , Shenggang Ying , Mingsheng Ying

Many quantum states arising in algorithms and physical systems occupy only a small, structured subset of the exponentially large Hilbert space, yet standard quantum state tomography fails to exploit this structure. We present an efficient…

Quantum Physics · Physics 2025-12-24 Chi-Kwong Li , Kevin Yipu Wu , Zherui Zhang

Using results from quantum filtering theory and methods from classical control theory, we derive an optimal control strategy for an open two-level system (a qubit in interaction with the electromagnetic field) controlled by a laser. The aim…

Quantum Physics · Physics 2009-11-10 Luc Bouten , Simon Edwards , V P Belavkin

In [1] Zhu and Rabitz presented a rapidly convergent iterative algorithm for optimal control of the expectation value of a positive definite observable in a pure-state quantum system. In this paper we generalize this algorithm to a quantum…

Quantum Physics · Physics 2009-10-31 S. G. Schirmer , M. D. Girardeau , J. V. Leahy

We consider the problem of certification of arbitrary ensembles of pure states and projective measurements solely from the experimental statistics in the prepare-and-measure scenario assuming the upper bound on the dimension of the Hilbert…

Quantum Physics · Physics 2021-04-07 Nikolai Miklin , Michał Oszmaniec

There has been an extensive development in the use of multi-partite entanglement as a resource for various quantum information processing tasks. In this paper we focus on preparing arbitrary spin eigenstates whose subset contain important…

Quantum Physics · Physics 2020-08-18 Amritesh Sharma , Ashwin A. Tulapurkar

Quantum feedback control protocols can improve the operation of quantum devices. Here we examine the performance of a purification protocol when there are imperfections in the controls. The ideal feedback protocol produces an $x$ eigenstate…

Quantum Physics · Physics 2011-08-11 Joshua Combes , Howard M. Wiseman

Accurate control of quantum states is crucial for quantum computing and other quantum technologies. In the basic scenario, the task is to steer a quantum system towards a target state through a sequence of control operations. Determining…

Quantum Physics · Physics 2024-06-14 Yan Zhu , Tailong Xiao , Guihua Zeng , Giulio Chiribella , Ya-Dong Wu

We present a deterministic framework for preparing an arbitrary three-qubit pure state. To leverage entanglement structure in the state-preparation task, we classify three-qubit pure states into five types with respect to a $1|2$…

Quantum Physics · Physics 2026-03-03 Yonghae Lee , Taewan Kim

A Markovian open quantum system which relaxes to a unique steady state $\rho_{ss}$ of finite rank can be decomposed into a finite physically realizable ensemble (PRE) of pure states. That is, as shown by Karasik and Wiseman [Phys. Rev.…

Mesoscale and Nanoscale Physics · Physics 2016-02-22 Shakib Daryanoosh , Howard M. Wiseman , Tobias Brandes

Quantum Optimal Control (QOC) supports the advance of quantum technologies by tackling its problems at the pulse level: Numerical approaches iteratively work towards a given target by parametrising the applied time-dependent fields with a…

Quantum Physics · Physics 2025-08-05 Alice Pagano , Matthias M Müller , Tommaso Calarco , Simone Montangero , Phila Rembold

We propose a quantum optimal control framework based on the Pontryagin Maximum Principle to design energy- and time-efficient pulses for open quantum systems. By formulating the Langevin equation of a dissipative LC circuit as a linear…

Quantum Physics · Physics 2024-12-31 Mo Zhou , F. A. Cárdenas-López , Sugny Dominique , Xi Chen

We show that optimizing a quantum gate for an open quantum system requires the time evolution of only three states irrespective of the dimension of Hilbert space. This represents a significant reduction in computational resources compared…

Quantum Physics · Physics 2021-02-16 Michael H. Goerz , Daniel M. Reich , Christiane P. Koch

The capability to control molecular rotation for field-free orientation, which arranges molecules in specific spatial directions without external fields, is crucial in physics, chemistry, and quantum information science. However,…

Quantum Physics · Physics 2025-12-25 Qian-Qian Hong , Zhe-Jun Zhang , Chuan-Cun Shu , Jun He , Daoyi Dong , Dajun Ding

We study quantum information processing by means of optimal control theory. To this end, we analyze the damped Jaynes-Cummings model, and derive optimal control protocols that minimize the heating or energy dispersion rates, and controls…

Quantum Physics · Physics 2014-07-14 Sebastian Deffner

Quantum many-body control is a central milestone en route to harnessing quantum technologies. However, the exponential growth of the Hilbert space dimension with the number of qubits makes it challenging to classically simulate quantum…

Quantum Physics · Physics 2023-07-26 Friederike Metz , Marin Bukov

We study reachable sets of open n-qubit quantum systems, whose coherent parts are under full unitary control, by adding as a further degree of incoherent control switchable Markovian noise on a single qubit. In particular, adding bang-bang…

Quantum Physics · Physics 2017-04-24 Ville Bergholm , F. K. Wilhelm , T. Schulte-Herbrueggen

We propose a feedback control scheme for generating and stabilizing pure states of transport devices, such as charge qubits, under non-equilibrium conditions. The purification of the device state is conditioned on single electron jumps and…

Mesoscale and Nanoscale Physics · Physics 2011-08-23 Christina Pöltl , Clive Emary , Tobias Brandes

In this paper an extended scalability condition is proposed to achieve the ground-state stability for a class of multipartite quantum systems which may involve two-body interactions, and an explicit procedure to construct the dissipation…

Quantum Physics · Physics 2016-11-02 Yu Pan , Thien Nguyen

Measurements are a primitive for characterizing quantum systems. Reducing the time taken to perform a measurement may be beneficial in many areas of quantum information processing. We show that permuting the eigenvalues of the state matrix…

Quantum Physics · Physics 2015-02-10 Joshua Combes , Aaron Denney , Howard M. Wiseman