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Related papers: On the Role of Hadamard Gates in Quantum Circuits

200 papers

Variational quantum algorithms have been advocated as promising candidates to solve combinatorial optimization problems on near-term quantum computers. Their methodology involves transforming the optimization problem into a quadratic…

Quantum Physics · Physics 2023-08-01 Zoé Verchère , Sourour Elloumi , Andrea Simonetto

Quantum circuits consisting of Clifford and matchgates are two classes of circuits that are known to be efficiently simulatable on a classical computer. We introduce a unified framework that shows in a transparent way the special structure…

Quantum Physics · Physics 2024-05-24 Igor Ermakov , Oleg Lychkovskiy , Tim Byrnes

Scaling up quantum computing hardware is hindered by the narrow operating margins of current quantum components. Here, we introduce a composite qubit and gate scheme that achieves wide margins by use of transistor-like nonlinearities to…

Quantum Physics · Physics 2022-02-23 Ryan J. Epstein

We show that the quantum logic gates, {\it viz.} the single qubit Hadamard and Phase Shift gates, can also be realised using q-deformed angular momentum states constructed via the Jordan-Schwinger mechanism with two q-deformed oscillators.…

Quantum Physics · Physics 2007-05-23 Debashis Gangopadhyay , Mahendra Nath Sinha Roy

We propose a universal quantum computing scheme in which the orthogonal qubit states $|0>$ and $|1>$ are identical in their single-particle spin and charge properties. Each qubit is contained in a single quantum dot and gate operations are…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Jordan Kyriakidis , Guido Burkard

In this paper we study the ways to use a global entangling operator to efficiently implement circuitry common to a selection of important quantum algorithms. In particular, we focus on the circuits composed with global Ising entangling…

Quantum Physics · Physics 2018-03-28 Dmitri Maslov , Yunseong Nam

We introduce a framework for simulating hybrid oscillator-qubit quantum processors on qubit-only systems through position encoding. By encoding continuous-variable position and momentum wave functions into qubit amplitudes, our method…

Quantum Physics · Physics 2026-03-11 Xi Lu , Bojko N. Bakalov , Yuan Liu

We present a general strategy for mapping fermionic systems to quantum hardware with square qubit connectivity which yields low-depth quantum circuits, counted in the number of native two-qubit fSIM gates. We achieve this by leveraging…

Quantum Physics · Physics 2024-05-01 Manuel G. Algaba , P. V. Sriluckshmy , Martin Leib , Fedor Šimkovic

Near term quantum computers with a high quantity (around 50) and quality (around 0.995 fidelity for two-qubit gates) of qubits will approximately sample from certain probability distributions beyond the capabilities of known classical…

Quantum Physics · Physics 2018-01-23 Sergio Boixo , Sergei V. Isakov , Vadim N. Smelyanskiy , Hartmut Neven

This article focuses on the development of scalable and quantum bit-efficient algorithms for computing power functions of random quantum states. Two algorithms, based on Hadamard testing and Gate Set Tomography, are proposed. We provide a…

Quantum Physics · Physics 2023-12-27 Wencheng Zhao , Tingting Chen , Ruyu Yang

In this paper, we present the experimental realization of multi-qubit gates $% \Lambda_n(not) $ in macroscopic ensemble of three-qubit and four-qubit molecules. Instead of depending heavily on the two-bit universal gate, which served as the…

Quantum Physics · Physics 2009-11-06 J. F. Du , M. J. Shi , J. H. Wu , X. Y. Zhou , R. D. Han

One of the key challenges in quantum information is coherently manipulating the quantum state. However, it is an outstanding question whether control can be realized with low error. Only gates from the Clifford group -- containing $\pi$,…

Quantum walk has been regarded as a primitive to universal quantum computation. By using the operations required to describe the single particle discrete-time quantum walk on a position space we demonstrate the realization of the universal…

Quantum Physics · Physics 2021-06-16 Shivani Singh , Prateek Chawla , Anupam Sarkar , C. M. Chandrashekar

A quantum circuit is generalized to a nonunitary one whose constituents are nonunitary gates operated by quantum measurement. It is shown that a specific type of one-qubit nonunitary gates, the controlled-NOT gate, as well as all one-qubit…

Quantum Physics · Physics 2011-01-11 Hiroaki Terashima , Masahito Ueda

We describe an efficient quantum algorithm for the quantum Schur transform. The Schur transform is an operation on a quantum computer that maps the standard computational basis to a basis composed of irreducible representations of the…

Quantum Physics · Physics 2024-08-22 William M. Kirby , Frederick W. Strauch

Simulation of quantum matters is a significant application of quantum computers. In contrast to the unitary operation which can be realized naturally on a quantum computer, the implementation of nonunitary operation, widely used in…

Quantum Physics · Physics 2021-12-21 Tong Liu , Jin-Guo Liu , Heng Fan

In order to achieve speedup over conventional classical computing for finding solution of computationally hard problems, quantum computing was introduced. Quantum algorithms can be simulated in a pseudo quantum environment, but…

Emerging Technologies · Computer Science 2020-07-15 Mrityunjay Ghosh , Nivedita Dey , Debdeep Mitra , Amlan Chakrabarti

The difference between classical and quantum algorithms (QA) is following: problem solved by QA is coded in the structure of the quantum operators. Input to QA in this case is always the same. Output of QA says which problem coded. In some…

Quantum Physics · Physics 2023-04-27 Sergey V. Ulyanov , Viktor S. Ulyanov

As the field of quantum computing grows, novel algorithms which take advantage of quantum phenomena need to be developed. As we are currently in the NISQ (noisy intermediate scale quantum) era, quantum algorithm researchers cannot reliably…

Quantum Physics · Physics 2024-11-28 Youssef Moawad , Andrew Brown , René Steijl , Wim Vanderbauwhede

We propose an effective set of elementary quantum gates which provide an encoded universality and demonstrate the physical feasibility of these gates for the solid-state quantum computer based on the multi-atomic systems in the QED cavity.…

Quantum Physics · Physics 2011-09-05 Farid Ablayev , Sergey Andrianov , Sergey Moiseev , Alexander Vasiliev