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Related papers: Unitary operator bases as universal averaging sets

200 papers

Quantum algorithms designed for realistic quantum many-body systems, such as chemistry and materials, usually require a large number of measurements of the Hamiltonian. Exploiting different ideas, such as {importance sampling,} observable…

Quantum Physics · Physics 2023-01-18 Bujiao Wu , Jinzhao Sun , Qi Huang , Xiao Yuan

Universal compilation is a training process that compiles a trainable unitary into a target unitary and it serves vast potential applications from quantum dynamic simulations to optimal circuits with deep-compressing, device benchmarking,…

Quantum Physics · Physics 2022-04-26 Vu Tuan Hai , Le Bin Ho

We investigate protocols for generating a state $t$-design by using a fixed separable initial state and a diagonal-unitary $t$-design in the computational basis, which is a $t$-design of an ensemble of diagonal unitary matrices with random…

Quantum Physics · Physics 2014-05-27 Yoshifumi Nakata , Masato Koashi , Mio Murao

We present a general framework for the generation of random unitaries based on random quenches in atomic Hubbard and spin models, forming approximate unitary $n$-designs, and their application to the measurement of R\'enyi entropies. We…

Quantum Physics · Physics 2018-02-06 B. Vermersch , A. Elben , M. Dalmonte , J. I. Cirac , P. Zoller

The main aim of this work is to present an explicit construction of a 2-design of ${\rm U}(2)$, relying only on a tool that belongs to every physicists toolbox: the theory of angular momentum. Unitary designs are a rich and fundamental…

Quantum Physics · Physics 2025-09-23 Rocco Maggi , Cosmo Lupo , Saverio Pascazio

An abstract formulation of quantum dynamics in the presence of a general set of quantum constraints is developed. Our constructive procedure is such that the relevant projection operator onto the physical Hilbert space is obtained with a…

High Energy Physics - Theory · Physics 2009-10-31 John R. Klauder

While quantum speed-up in solving certain decision problems by a fault-tolerant universal quantum computer has been promised, a timely research interest includes how far one can reduce the resource requirement to demonstrate a provable…

Quantum Physics · Physics 2018-01-01 Jacob Miller , Stephen Sanders , Akimasa Miyake

A certain generalization of the mathematical formalism of quantum mechanics beyond operator algebras is considered. The approach is based on the concept of conditional probability and the interpretation of the Lueders - von Neumann quantum…

Mathematical Physics · Physics 2010-01-21 Gerd Niestegge

We introduce a framework for online structure theory. Our approach generalises notions arising independently in several areas of computability theory and complexity theory. We suggest a unifying approach using operators where we allow the…

Logic · Mathematics 2023-06-22 Rod Downey , Alexander Melnikov , Keng Meng Ng

Motivated by the recent rapid development of complexity theory applied to quantum mechanical processes we present the complete derivation of Nielsen's complexity of unitaries belonging to the representations of oscillator group. Our…

Quantum Physics · Physics 2025-12-22 K. Andrzejewski , K. Bolonek-Lasoń , P. Kosiński

We present a systematic construction of quantum circuits implementing Grover's database search algorithm for arbitrary number of targets. We introduce a new operator which flips the sign of the targets and evaluate its circuit complexity.…

Quantum Physics · Physics 2011-10-31 Yuji Tanaka , Tsubasa Ichikawa , Masahito Tada-Umezaki , Yukihiro Ota , Mikio Nakahara

We consider the general measurement scenario in which the ensemble average of an operator is determined via suitable data-processing of the outcomes of a quantum measurement described by a POVM. After reviewing the optimization of data…

Quantum Physics · Physics 2007-05-23 Paolo Perinotti , Giacomo M. D'Ariano

Mathematical core of quantum mechanics is the theory of unitary representations of symmetries of physical systems. We argue that quantum behavior is a natural result of extraction of "observable" information about systems containing…

Quantum Physics · Physics 2011-10-03 Vladimir V. Kornyak

Renormalization group ideas and effective operators are used to efficiently determine localized unitaries for preparing the ground states of non-interacting scalar field theories on digital quantum devices. With these methods, classically…

Quantum Physics · Physics 2020-12-30 Natalie Klco , Martin J. Savage

Quantum operations are the most widely used tool in the theory of quantum information processing, representing elementary transformations of quantum states that are composed to form complex quantum circuits. The class of quantum…

Quantum Physics · Physics 2018-07-25 Paolo Perinotti

We relate extensions of completely unitary VOAs and (commutative) Q-systems. As an application, we show that any unitary extension of a completely unitary VOA is completely unitary.

Quantum Algebra · Mathematics 2026-01-21 Bin Gui

In these lectures we develop the projection operator method for quantum groups. Here the term "quantum groups" means q-deformed universal enveloping algebras of contragredient Lie (super)algebras of finite growth. Contains of the lectures…

Quantum Algebra · Mathematics 2007-05-23 V. N. Tolstoy

Quantum state preparation in high-dimensional systems is an essential requirement for many quantum-technology applications. The engineering of an arbitrary quantum state is, however, typically strongly dependent on the experimental platform…

Quantum computers leverage the principles of quantum mechanics to do computation with a potential advantage over classical computers. While a single classical computer transforms one particular binary input into an output after applying one…

Emerging Technologies · Computer Science 2025-03-17 Francisco Chicano , Gabiel Luque , Zakaria Abdelmoiz Dahi , Rodrigo Gil-Merino

Based on the group structure of a unitary Lie algebra, a scheme is provided to systematically and exhaustively generate quantum error correction codes, including the additive and nonadditive codes. The syndromes in the process of…

Quantum Physics · Physics 2013-11-01 Ming-Chung Tsai , Po-Chung Chen , Kuan-Peng Chen , Zheng-Yao Su