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Related papers: Numerical test of few-qubit clock protocols

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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

Noisy, intermediate-scale quantum computers come with intrinsic limitations in terms of the number of qubits (circuit "width") and decoherence time (circuit "depth") they can have. Here, for the first time, we demonstrate a recently…

Quantum Physics · Physics 2020-09-02 Thomas Ayral , François-Marie Le Régent , Zain Saleem , Yuri Alexeev , Martin Suchara

With quantum devices rapidly approaching qualities and scales needed for fault tolerance, the validity of simplified error models underpinning the study of quantum error correction needs to be experimentally evaluated. In this work, we have…

Quantum Physics · Physics 2024-12-11 Spiro Gicev , Lloyd C. L. Hollenberg , Muhammad Usman

Quantum computing is an emerging technology that has the potential to achieve exponential speedups over their classical counterparts. To achieve quantum advantage, quantum principles are being applied to fields such as communications,…

Quantum Physics · Physics 2024-04-19 Arijit Mondal , Keshab K. Parhi

In this work, we studied the relaxation dynamics of coherences of different order present in a system of two coupled nuclear spins. We used a previously designed model for intrinsic noise present in such systems which considers the Lindblad…

Quantum Physics · Physics 2022-07-12 Harpreet Singh , Arvind , Kavita Dorai

We investigate different quantum parameter estimation scenarios in the presence of noise, and identify optimal probe states. For frequency estimation of local Hamiltonians with dephasing noise, we determine optimal probe states for up to 70…

Quantum Physics · Physics 2014-08-10 F. Fröwis , M. Skotiniotis , B. Kraus , W. Dür

In this paper, we describe a tensor network simulation of a neutral atom quantum system under the presence of noise, while introducing a new purity-preserving truncation technique that compromises between the simplicity of the matrix…

Quantum Physics · Physics 2025-06-03 James Allen , Matthew Otten , Stephen Gray , Bryan K. Clark

Quantum projection noise will soon limit the best achievable precision of optical atomic clocks based on lattice-confined neutral atoms. Squeezing the collective atomic pseudo-spin via measurement of the clock state populations during…

Quantum Physics · Physics 2009-11-13 D. Meiser , Jun Ye , M. J. Holland

We present a method for characterizing the performance of noisy quantum processors using discrete time crystals. Deviations from ideal persistent oscillatory behavior give rise to numerical scores by which relative quantum processor…

Quantum Physics · Physics 2023-01-19 Victoria Zhang , Paul D. Nation

The long-time maintenance of quantum coherence is crucial for its practical applications. We explore decoherence process of a multiqubit system passing through a correlated channel (phase flip, bit flip, bit-phase flip, and depolarizing).…

Quantum Physics · Physics 2020-02-06 Ming-Liang Hu , Heng Fan

Protocols for quantum measurement are an essential part of quantum computing. Measurements are no longer confined to the final step of computation but are increasingly embedded within quantum circuits as integral components of…

Quantum Physics · Physics 2025-11-07 Michal Krejčí , Lucie Krejčí , Ijaz Ahamed Mohammad , Martin Plesch , Martin Friák

Quantum data is susceptible to decoherence induced by the environment and to errors in the hardware processing it. A future fault-tolerant quantum computer will use quantum error correction (QEC) to actively protect against both. In the…

Quantum Physics · Physics 2015-04-30 D. Ristè , S. Poletto , M. -Z. Huang , A. Bruno , V. Vesterinen , O. -P. Saira , L. DiCarlo

The dynamics of a quantum anharmonic oscillator whose position is monitored by a Bose-Einstein condensate (BEC) trapped in a symmetric double well potential is studied. The (non-exponential) decoherence induced on the oscillator by the…

Quantum Physics · Physics 2014-10-29 D. Alonso , S. Brouard , D. Sokolovski

We show that the decoherence, which in the long run destroys quantum features of a system, can be used to reveal the entanglement in a two-qubit system. To this end, we consider a criterion that formally resembles the…

Quantum Physics · Physics 2018-09-07 Jan Krzywda , Piotr Szańkowski , Jan Chwedeńczuk , Łukasz Cywiński

Variational algorithms may enable classically intractable simulations on near-future quantum computers. However, their potential is limited by hardware errors. It is therefore crucial to develop efficient ways to mitigate these errors.…

Quantum Physics · Physics 2019-05-29 Sam McArdle , Xiao Yuan , Simon Benjamin

Optical atomic clocks are our most precise tools to measure time and frequency. They enable precision frequency comparisons between atoms in separate locations to probe the space-time variation of fundamental constants, the properties of…

Atomic Physics · Physics 2022-09-09 B. C. Nichol , R. Srinivas , D. P. Nadlinger , P. Drmota , D. Main , G. Araneda , C. J. Ballance , D. M. Lucas

Neutral-atom arrays trapped in optical potentials are a powerful platform for studying quantum physics, combining precise single-particle control and detection with a range of tunable entangling interactions. For example, these capabilities…

We experimentally demonstrate the coherent manipulation of atomic states in far-detuned dipole traps and registers of dipole traps based on two-dimensional arrays of microlenses. By applying Rabi, Ramsey, and spin-echo techniques, we…

Quantum Physics · Physics 2007-05-23 A. Lengwenus , J. Kruse , M. Volk , W. Ertmer , G. Birkl

Quantum dynamics on curved spacetime has never been directly probed beyond the Newtonian limit. Although we can describe such dynamics theoretically, experiments would provide empirical evidence that quantum theory holds even in this…

Quantum Physics · Physics 2025-07-22 Jacob P. Covey , Igor Pikovski , Johannes Borregaard

In secure quantum communication protocols, a set of single qubits prepared using 2 or more mutually unbiased bases or a set of $n$-qubit ($n\geq2$) entangled states of a particular form are usually used to form a verification string which…

Quantum Physics · Physics 2022-06-10 Rishi Dutt Sharma , Kishore Thapliyal , Anirban Pathak , Alok Kumar Pan , Asok De