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Related papers: Magic composite pulses

200 papers

We introduce universal broadband composite pulse sequences for robust high-fidelity population inversion in two-state quantum systems, which compensate deviations in any experimental parameter (e.g. pulse amplitude, pulse duration, detuning…

Quantum Physics · Physics 2015-06-19 Genko T. Genov , Daniel Schraft , Thomas Halfmann , Nikolay V. Vitanov

We introduce a novel control method for robust quantum information processing suited for quantum integrated photonics. We utilize off-resonant detunings as control parameters to derive a new family of composite pulses for high-fidelity…

Quantum Physics · Physics 2019-10-02 Elica Kyoseva , Hadar Greener , Haim Suchowski

We present a protocol to selectively decouple, recouple, and engineer effective couplings in mesoscopic dipolar spin networks. In particular, we develop a versatile protocol that relies upon magic angle spinning to perform Hamiltonian…

Quantum Physics · Physics 2019-01-16 Ashok Ajoy , Ulf Bissbort , Dario Poletti , Paola Cappellaro

We present a remarkable finding that a recently discovered [G. S. Uhrig, Phys. Rev. Lett. 98, 100504 (2007)] series of pulse sequences, designed to optimally restore coherence to a qubit in the spin-boson model of decoherence, is in fact…

Quantum Physics · Physics 2009-11-13 B. Lee , W. M. Witzel , S. Das Sarma

The simulation of nuclear magnetic resonance (NMR) experiments is a notoriously difficult task, if many spins participate in the dynamics. The recently established dynamic mean-field theory for high-temperature spin systems (spinDMFT)…

Chemical Physics · Physics 2026-02-04 Timo Gräßer , Götz S. Uhrig

The nuclear spins in nanostructured semiconductors play a central role in quantum applications. The nuclear spins represent a useful resource for generating local magnetic fields but nuclear spin noise represents a major source of dephasing…

In the framework of nuclear magnetic resonance, we consider the general problem of the coherent control of a spin coupled to a bath by means of composite or continuous pulses of duration $\tau_\mathrm{p}$. We show explicity that it is…

Quantum Physics · Physics 2010-03-16 S. Pasini , P. Karbach , C. Raas , G. S. Uhrig

We describe a simple scheme for calculating the fidelity of a composite pulse when considered as a universal rotor.

Quantum Physics · Physics 2007-05-23 M. D. Bowdrey , J. A. Jones

For the implementation of a quantum computer it is necessary to exercise complete control over the Hamiltonian of the used physical system. For NMR quantum computing the effectively acting Hamiltonian can be manipulated via pulse sequences.…

Quantum Physics · Physics 2009-11-07 Marcus Stollsteimer , Guenter Mahler

A mechanism is advanced suggesting the resolution of the dichotomy of long-lived spin polarization storage versus fast spin reversal at the required time. A system of atoms or molecules is considered interacting through magnetic dipolar…

Mesoscale and Nanoscale Physics · Physics 2018-11-14 V. I. Yukalov , E. P. Yukalova

We report simulations of a frustrated odd-numbered macrospin ring system, with full point dipolar interactions, driven by a rotating uniform applied magnetic field of constant magnitude. The system is designed with equally-spaced…

Materials Science · Physics 2014-09-23 J. P. Morgan , R. P. Cowburn

Controlling ensembles of weakly coupled spins typically requires computationally expensive multispin optimisations. We present a compact framework that enables control of weakly coupled spin systems (of any spin), but using RF pulses…

Quantum Physics · Physics 2026-02-12 Suzanne Lim , Bowen Guo , Abi Turner , Charles Buchanan , Andrew Baldwin , Jonathan A. Jones

Spin engineering of advanced pulse sequences has had a transformative impact on the development of nuclear magnetic resonance (NMR) spectroscopy, to an extending degree also electron paramagnetic resonance (EPR), and the hybrid between the…

Chemical Physics · Physics 2025-01-31 Jose P. Carvalho , Anders Bodholt Nielsen , Eniko Baligacs , Nino Wili , Niels Chr. Nielsen

General relativity predicts that two counter-orbiting clocks around a spinning mass differ in the time required to complete the same orbit. The difference in these two values for the orbital period is generally referred to as the…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Kaye Jiale Li , Kinwah Wu , Ziri Younsi , Joana Teixeira , Dinesh Singh

We analyze the simultaneous time-optimal control of two-spin systems. The two non coupled spins which differ in the value of their chemical offsets are controlled by the same magnetic fields. Using an appropriate rotating frame, we restrict…

Quantum Physics · Physics 2015-05-19 E. Assemat , M. Lapert , Y. Zhang , M. Braun , S. J. Glaser , D. Sugny

A general theoretical description of a magnetic resonance is presented. This description is necessary for a detailed analysis of spin dynamics in electric-dipole-moment experiments in storage rings. General formulas describing a behavior of…

Nuclear Theory · Physics 2017-05-30 Alexander J. Silenko

Dipolar spin ensembles with random spin positions attract much attention currently because they help to understand decoherence as it occurs in solid state quantum bits in contact with spin baths. Also, these ensembles are systems which may…

Disordered Systems and Neural Networks · Physics 2023-12-08 Timo Gräßer , Kristine Rezai , Alexander O. Sushkov , Götz S. Uhrig

Experiments in coherent spectroscopy correspond to control of quantum mechanical ensembles guiding them from initial to final target states. The control inputs (pulse sequences) that accomplish these transformations should be designed to…

Quantum Physics · Physics 2009-11-07 Navin Khaneja , Timo Reiss , Burkhard Luy , Steffen J. Glaser

We evaluate various sources of errors that occur when attempting to produce a specified coherent change of a two-state quantum system using six popular coherent control techniques: resonant excitation, adiabatic following, composite…

Quantum Physics · Physics 2021-03-24 Boyan T. Torosov , Bruce W. Shore , Nikolay V. Vitanov

We address a problem of generating a robust entangling gate between electronic and nuclear spins in the system of a single nitrogen-vacany centre coupled to a nearest Carbon-13 atom in diamond against certain types of systematic errors such…

Quantum Physics · Physics 2010-07-14 R. S. Said , J. Twamley