English
Related papers

Related papers: CHSH Violations using Dynamic Circuits

200 papers

Clauser-Horne-Shimony-Holt inequality for bipartite systems of 4-dimension is studied in detail by employing the unbiased eight-port beam splitters measurements. The uniform formulae for the maximum and minimum values of this inequality for…

Quantum Physics · Physics 2007-05-23 Li-Bin Fu , Jing-Ling Chen , Shi-Gang Chen

In this paper, we propose a novel method using Deep Neural Networks (DNNs) to optimise the parameters of pulse waveforms used for manipulating qubit states, resulting in high fidelity implementation of qubit gates. High fidelity quantum…

Quantum Physics · Physics 2024-08-06 Zachary Fillingham , Hossein Nevisi , Shirin Dora

Maximally entangled states should maximally violate the Bell inequality. In this paper, it is proved that all two-qubit states that maximally violate the Bell-Clauser-Horne-Shimony-Holt inequality are exactly Bell states and the states…

Quantum Physics · Physics 2009-11-10 Zeqian Chen

The relation between Bell-CHSH violation and factorization of Hilbert space is considered here. That is, a state which is local in the sense of the Bell-CHSH inequality under a certain factorization of the underlying Hilbert space can be…

Superior computational power promised by quantum computers utilises the fundamental quantum mechanical principle of entanglement. However, achieving entanglement and verifying that the generated state does not follow the principle of local…

Accurate ground-state calculations on noisy quantum computers are fundamentally limited by restricted ansatz expressivity and unavoidable hardware errors. We introduce a hybrid-quantum classical framework that simultaneously addresses these…

A CNOT circuit is the key gadget for entangling qubits in quantum computing systems. However, the qubit connectivity of noisy intermediate-scale quantum (NISQ) devices is constrained by their {limited connectivity architecture}. To improve…

Quantum Physics · Physics 2023-02-03 Bujiao Wu , Xiaoyu He , Shuai Yang , Lifu Shou , Guojing Tian , Jialin Zhang , Xiaoming Sun

Traditionally, quantum entanglement has played a central role in foundational discussions of quantum mechanics. The measurement of correlations between entangled particles can exhibit results at odds with classical behavior. These…

Mesoscale and Nanoscale Physics · Physics 2012-03-15 L. DiCarlo , M. D. Reed , L. Sun , B. R. Johnson , J. M. Chow , J. M. Gambetta , L. Frunzio , S. M. Girvin , M. H. Devoret , R. J. Schoelkopf

Quantum computing hardware is affected by quantum noise that undermine the quality of results of an executed quantum program. Amongst other quantum noises, coherent error that caused by parameter drifting and miscalibration, remains…

Hardware Architecture · Computer Science 2024-10-15 Xiangyu Ren , Junjie Wan , Zhiding Liang , Antonio Barbalace

Semiconductor quantum dots in silicon are promising qubits because of long spin coherence times and their potential for scalability. However, such qubits with complete electrical control and fidelities above the threshold for quantum error…

Mesoscale and Nanoscale Physics · Physics 2016-03-23 Clement H. Wong

We give analytical solutions for the time-optimal synthesis of entangling gates between indirectly coupled qubits 1 and 3 in a linear spin chain of three qubits subject to an Ising Hamiltonian interaction with equal coupling $J$ plus a…

Quantum Physics · Physics 2014-12-01 A. Carlini , A. Hosoya , T. Koike , Y. Okudaira

Self-testing protocols enable the certification of quantum systems in a device-independent manner, i.e. without knowledge of the inner workings of the quantum devices under test. Here, we demonstrate this high standard for characterization…

Quantum non-locality is an important concept in quantum physics. In this work, we study the quantum non-locality in a fermion many-body system under quasi-periodic disorders. The Clauser-Horne-Shimony-Holt (CHSH) inequality is…

Disordered Systems and Neural Networks · Physics 2024-10-08 Yoshihito Kuno

The author analyzes quantum computation with the hybrid qubit (HQ) that is encoded using the three-electron configuration of a double quantum dot. All gate operations are controlled with electric signals, while the qubit remains at an…

Mesoscale and Nanoscale Physics · Physics 2015-07-14 Sebastian Mehl

Collective measurements on large quantum systems together with a majority voting strategy can lead to a violation of the CHSH Bell inequality. In presence of many entangled pairs, this violation decreases quickly with the number of pairs,…

We construct a fault-tolerant quantum error-correcting protocol based on a qubit encoded in a large spin qudit using a spin-cat code, analogous to the continuous variable cat encoding. With this, we can correct the dominant error sources,…

Bell nonlocality and Kochen-Specker contextuality are two remarkable nonclassical features of quantum theory, related to strong correlations between outcomes of measurements performed on quantum systems. Both phenomena can be witnessed by…

The increasing depth of quantum circuits presents a major limitation for the execution of quantum algorithms, as the limited coherence time of physical qubits leads to noise that manifests as errors during computation. In this work, we…

Quantum Physics · Physics 2026-03-24 Spyros Tserkis , Muhammad Umer , Dimitris G. Angelakis

In two-mode interferometry, for a given total photon number $N$, entangled Fock state superpositions of the form $(|N-m\rangle_a|m\rangle_b+e^{i (N-2m)\phi}|m\rangle_a|N-m\rangle_b)/\sqrt{2}$ have been considered for phase estimation.…

High-dimensional quantum entanglement is drawing attention because it enables us to perform quantum information tasks that are robust against noises. To test the nonlocality of entangled qudits, the Collins-Gisin-Linden-Massar-Popescu…

Quantum Physics · Physics 2016-02-05 Takuya Ikuta , Hiroki Takesue