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Related papers: Reservoir-Free Decoherence in Flying Qubits

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Achieving very fast gates that undercut the natural limits set by decoherence requires going into the strong driving limit. Realizing single-qubit control predicted beyond semi-classical, time-dependent modeling has yet to be experimentally…

We consider error suppression schemes in which quantum information is encoded into the ground subspace of a Hamiltonian comprising a sum of commuting terms. Since such Hamiltonians are gapped they are considered natural candidates for…

Quantum Physics · Physics 2015-01-09 Iman Marvian , Daniel A. Lidar

We show that quantum properties of spacetime, encoded by noncommutativity at the Planck scale, lead to a generalized time evolution of quantum systems in which pure states can evolve into mixed states. Specifically, a decoherence mechanism…

General Relativity and Quantum Cosmology · Physics 2023-01-27 Michele Arzano , Vittorio D'Esposito , Giulia Gubitosi

Obtaining high-fidelity and robust quantum gates is the key for scalable quantum computation, and one of the promising ways is to implement quantum gates using geometric phases, where the influence of local noises can be greatly reduced. To…

Quantum Physics · Physics 2021-10-07 Zhi-Cheng He , Zheng-Yuan Xue

The stabilizing properties of one-error correcting jump codes are explored under realistic non-ideal conditions. For this purpose the quantum algorithm of the tent-map is decomposed into a universal set of Hamiltonian quantum gates which…

Quantum Physics · Physics 2007-05-23 Oliver Kern , Gernot Alber

The decoherence of a qubit due to a classical non-Gaussian noise with correlation time longer than the decoherence time is discussed for arbitrary working points of the qubit. A method is developed that allows an exact formula for the phase…

Superconductivity · Physics 2009-11-11 J. Bergli , Y. M. Galperin , B. L. Altshuler

There is a natural orthogonal basis of the 6-qubit decoherence-free (DF) space robust against collective noise. Interestingly, most of the basis states can be obtained from one another just permuting qubits. This property: (a) is useful for…

Quantum Physics · Physics 2009-07-28 Adan Cabello

The effects of decoherence on the transfer and storage of coherent quantum states in hybrid systems are studied within the Caldeira-Leggett approach. In general, we find that a high transfer fidelity can be achieved even if the decoherence…

Quantum Physics · Physics 2013-04-24 Kelly R. Patton , Uwe R. Fischer

Motivated by recent work showing that a quantum error correcting code can be generated by hybrid dynamics of unitaries and measurements, we study the long time behavior of such systems. We demonstrate that even in the "mixed" phase, a…

Quantum Physics · Physics 2022-08-02 Lukasz Fidkowski , Jeongwan Haah , Matthew B. Hastings

We present an approach that allows quantifying decoherence processes in an open quantum system subject to external time-dependent control. Interactions with the environment are modeled by a standard bosonic heat bath. We develop two…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Dmitry Solenov , Vladimir Privman

We study decoherence of propagating spin-1/2 excitations in generic (non-integrable and/or disordered) spin chains. We find the relevant decoherence times to be shorter in both the near-critical and diffusive regimes (if any), which fact…

Strongly Correlated Electrons · Physics 2009-11-10 D. V. Khveshchenko

The superconducting flux qubit has two quantum states with opposite magnetic flux. Environment of nuclear spins can find out the direction of the magnetic flux after a decoherence time $\tau_0$ inversely proportional to the magnitude of the…

Other Condensed Matter · Physics 2009-11-10 Jacek Dziarmaga

A central task towards building a practical quantum computer is to protect individual qubits from decoherence while retaining the ability to perform high-fidelity entangling gates involving arbitrary two qubits. Here we propose and…

A qubit (containing two quantum states, 1 and 2), is coupled to a control register (state 3), which is subject to telegraph noise. We study the time evolution of the density matrix $\rho$ of an electron which starts in some coherent state…

Mesoscale and Nanoscale Physics · Physics 2009-09-01 Amnon Aharony , Ora Entin-Wohlman , Sushanta Dattagupta

To protect a quantum system from decoherence due to interaction with its environment, we investigate the existence of initial states of the environment allowing for decoherence-free evolution of the system. For models in which a two-state…

Quantum Physics · Physics 2010-01-19 Olivier Landon-Cardinal , Richard MacKenzie

Implementing quantum operations in the form of natural Hamiltonian dynamics is desirable, since they almost require no external control or feedback. In this work, we propose a NISQ-friendly quantum-classical hybrid approach to designing a…

Quantum Physics · Physics 2024-09-23 Arunava Majumder , Dylan Lewis , Akshaya Jayashankar , V. S. Prasannaa , Sougato Bose

We consider finite-dimensional Markovian open quantum systems, and characterize the extent to which time-independent Hamiltonian control may allow to stabilize a target quantum state or subspace and optimize the resulting convergence speed.…

Quantum Physics · Physics 2015-03-17 Francesco Ticozzi , Riccardo Lucchese , Paola Cappellaro , Lorenza Viola

We investigate the effectiveness of different dynamical decoupling protocols for storage of a single qubit in the presence of a purely dephasing bosonic bath, with emphasis on comparing quantum coherence preservation under uniform vs.…

Quantum Physics · Physics 2015-05-14 Thomas E. Hodgson , Lorenza Viola , Irene D'Amico

The interaction of quantum emitters with one-dimensional photon-like reservoirs induces strong and long-range dissipative couplings that give rise to the emergence of so-called Decoherence Free Subspaces (DFS) which are decoupled from…

Quantum Physics · Physics 2016-08-01 V. Paulisch , H. J. Kimble , A. Gonzalez-Tudela

Any quantum system interacting with a complex environment undergoes decoherence. Empty space is filled with vacuum energy due to matter fields in their ground state and represents an underlying environment that any quantum particle has to…

General Relativity and Quantum Cosmology · Physics 2009-08-26 Paolo M. Bonifacio