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Related papers: Control of trapped-ion quantum states with optical…

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Today's quantum computers operate with a binary encoding that is the quantum analog of classical bits. Yet, the underlying quantum hardware consists of information carriers that are not necessarily binary, but typically exhibit a rich…

Ultracold molecules trapped in optical tweezers show great promise for the implementation of quantum technologies and precision measurements. We study a prototypical scenario where two interacting polar molecules placed in separate traps…

An infinite dimensional system such as a quantum harmonic oscillator offers a potentially unbounded Hilbert space for computation, but accessing and manipulating the entire state space requires a physically unrealistic amount of energy.…

Quantum Physics · Physics 2021-09-13 Yuan Liu , Jasmine Sinanan-Singh , Matthew T. Kearney , Gabriel Mintzer , Isaac L. Chuang

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

Control over physical systems at the quantum level is a goal shared by scientists in fields as diverse as metrology, information processing, simulation and chemistry. For trapped atomic ions, the quantized motional and internal degrees of…

Quantum Physics · Physics 2015-03-19 C. Ospelkaus , U. Warring , Y. Colombe , K. R. Brown , J. M. Amini , D. Leibfried , D. J. Wineland

A pulse of matter waves may dramatically change its shape when traversing an absorbing barrier with time-dependent transparency. Here we show that this effect can be utilized for controlled manipulation of spatially-localized quantum…

Quantum Physics · Physics 2015-05-04 Arseni Goussev

In finite dimensions, controllability of bilinear quantum control systems can be decided quite easily in terms of the "Lie algebra rank condition" (LARC), such that only the systems Lie algebra has to be determined from a set of generators.…

Quantum Physics · Physics 2018-12-24 Michael Keyl

Both the electron transport-based qubits, implemented through double quantum dots, and the sources of indistinguishable single-photons like self-assembled quantum dots are strong candidates for the implementation of quantum technologies,…

Mesoscale and Nanoscale Physics · Physics 2018-11-14 Ted S. Santana , Francisco A. G. Almeida

he multiqubit entangled states are coherently controlled in the quantum spin systems composed of $N+1$ interacting antiferromagnetic molecular rings. The tunable intermolecular couplings arise from the local exchange interactions between…

Quantum Physics · Physics 2009-03-17 Xiang Hao , Tao Pan , Taocheng Zang , Shiqun Zhu

Sufficient conditions for complete controllability of $N$-level quantum systems subject to a single control pulse that addresses multiple allowed transitions concurrently are established. The results are applied in particular to Morse and…

Quantum Physics · Physics 2009-11-06 S. G. Schirmer , H. Fu , A. I. Solomon

Single-qubit measurements are typically insufficient for inferring arbitrary quantum states of a multi-qubit system. We show that if the system can be fully controlled by driving a single qubit, then utilizing a local random pulse is almost…

Quantum Physics · Physics 2020-01-14 Pengcheng Yang , Min Yu , Ralf Betzholz , Christian Arenz , Jianming Cai

We investigate the controllability of an infinite-dimensional quantum system: a quantum particle confined on a Thick Quantum Graph, a generalisation of Quantum Graphs whose edges are allowed to be manifolds of arbitrary dimension with…

Mathematical Physics · Physics 2023-07-20 Aitor Balmaseda , Davide Lonigro , Juan Manuel Pérez-Pardo

In Coulomb 3-body problems, configurations of close proximity of the particles are classically unstable. In confined systems they might however exist as excited quantum states. Quantum control of such states by time changing electromagnetic…

Quantum Physics · Physics 2024-11-15 R. Vilela Mendes

Quantum Optimal Control Theory (QOCT) provides the necessary tools to theoretically design driving fields capable of controlling a quantum system towards a given state or along a prescribed path in Hilbert space. This theory must be…

Atomic and Molecular Clusters · Physics 2013-05-30 Alberto Castro , Jan Werschnik , Eberhard K. U. Gross

We present a theory of quantum optical control of an electron spin in a single semiconductor quantum dot via spin-flip Raman transitions. We show how an arbitrary spin rotation may be achieved by virtual excitation of discrete or continuum…

Condensed Matter · Physics 2009-11-10 Pochung Chen , C. Piermarocchi , L. J. Sham , D. Gammon , D. G. Steel

We show theoretically that by applying a bichromatic electromagnetic field, the dressed states of a monochromatically driven two-level atom can be pumped into a coherent superposition termed as dressed-state coherent population trapping.…

Optics · Physics 2008-11-20 Peng Li , Qun Zhang , Xi-Jing Ning , J. Q. You

Despite an apparent progress in implementing individual solid-state qubits, there have been no experimental reports so far on multi-bit gates required for building a real quantum computer. Here we report a new circuit comprising two coupled…

Mesoscale and Nanoscale Physics · Physics 2010-04-20 Yu. A. Pashkin , T. Yamamoto , O. Astafiev , Y. Nakamura , D. V. Averin , J. S. Tsai

An optimal dynamical decoupling of a quantum system coupled to a noisy environment must take into account also the imperfections of the control pulses. We present a new formalism which describes, in a closed-form expression, the evolution…

Quantum Physics · Physics 2016-10-19 Ido Almog , Gil Loewenthal , Jonathan Coslovsky , Yoav Sagi , Nir Davidson

Conventional approaches for controlling open quantum systems use coherent control which affects the system's evolution through the Hamiltonian part of the dynamics. Such control, although being extremely efficient for a large variety of…

Quantum Physics · Physics 2009-05-04 Alexander Pechen , Herschel Rabitz

Structured decompositions of a desired unitary operator are employed to derive control schemes that achieve certain control objectives for finite-level quantum systems using only sequences of simple control pulses such as square waves with…

Quantum Physics · Physics 2007-05-23 S. G. Schirmer , A. D. Greentree , V. Ramakrishna , H. Rabitz