English
Related papers

Related papers: Quantum circuits to measure scalar spin chirality

200 papers

We introduce a notion of chirality for generic quantum states. A chiral state is defined as a state which cannot be transformed into its complex conjugate in a local product basis using local unitary operations. We introduce a number of…

Quantum Physics · Physics 2025-03-17 Shreya Vardhan , Bowen Shi , Isaac H. Kim , Yijian Zou

The measurement of a spin-$\half$ is modeled by coupling it to an apparatus, that consists of an Ising magnetic dot coupled to a phonon bath. Features of quantum measurements are derived from the dynamical solution of the measurement,…

Quantum Physics · Physics 2017-08-23 Armen E. Allahverdyan , Roger Balian , Theo M. Nieuwenhuizen

We develop a family of chiral measures to quantify the chirality of a distribution and assign it a handedness. Our measures are built using the tensorial moments of the distribution, which naturally encode its spatial character, not only…

Data Analysis, Statistics and Probability · Physics 2026-03-31 Emilio Pisanty , Nicola Mayer , Andrés Ordóñez , Alexander Löhr , Margarita Khokhlova

In quantum computing, the indirect measurement of unitary operators such as the Hadamard test plays a significant role in many algorithms. However, in certain cases, the indirect measurement can be reduced to the direct measurement, where a…

Quantum Physics · Physics 2019-08-14 Kosuke Mitarai , Keisuke Fujii

Quantum spin liquids are fascinating phases of matter, hosting fractionalized spin excitations and unconventional long-range quantum entanglement. These exotic properties, however, also render their experimental characterization…

Strongly Correlated Electrons · Physics 2022-09-20 Wilhelm Kadow , Laurens Vanderstraeten , Michael Knap

An exactly solvable model for a quantum measurement is discussed, that integrates quantum measurements with classical measurements. The z-component of a spin-1/2 test spin is measured with an apparatus, that itself consists of magnet of N…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 A. E. Allahverdyan , R. Balian , Th. M. Nieuwenhuizen

We formulate a transparent measure that quantifies chirality in single electron ionization triggered in atoms, which are achiral systems. We do so in the context of Ar driven by a new type of optical fields that consists of two…

Atomic Physics · Physics 2021-12-07 G. P. Katsoulis , Z. Dube , P. Corkum , A. Staudte , A. Emmanouilidou

We present a quantum circuit that transforms an unknown three-qubit state into its canonical form, up to relative phases, given many copies of the original state. The circuit is made of three single-qubit parametrized quantum gates, and the…

The theory of angular momentum connects physical rotations and quantum spins together at a fundamental level. Physical rotation of a quantum system will therefore affect fundamental quantum operations, such as spin rotations in projective…

Quantum Physics · Physics 2020-01-22 Alexander A. Wood , Lloyd C. L. Hollenberg , Robert E. Scholten , Andy M. Martin

Chirality in condensed matter is now a topic of the utmost importance because of its significant role in the understanding and mastering of a large variety of new fundamental physicals mechanisms. Versatile experimental approaches, capable…

The quantum correlations of two or more entangled particles present the possibility of stronger-than-classical outcome coincidences. We investigate two-partite correlations of spin one, three-half and higher quanta in a state satisfying a…

Quantum Physics · Physics 2010-05-20 Karl Svozil

Many of the proposed solutions to the hierarchy and naturalness problems postulate new `partner' fields to the standard model particles. Determining the spins of these new particles will be critical in distinguishing among the various…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matthew R. Buckley , Hitoshi Murayama , William Klemm , Vikram Rentala

Quantum entanglement is one of the core features of quantum theory. While it is typically revealed by measurements along carefully chosen directions, here we review different methods based on so-called random or randomized measurements.…

Quantum Physics · Physics 2020-11-24 Lukas Knips

Quantum coherence is the most fundamental of all quantum quantifiers, underlying other well-known quantities such as entanglement, quantum discord, and Bell correlations. It can be distributed in a multipartite system in various ways -- for…

Quantum mechanics predicts that measurements of incompatible observables carry a minimum uncertainty which is independent of technical deficiencies of the measurement apparatus or incomplete knowledge of the state of the system. Nothing yet…

Quantum Physics · Physics 2013-06-14 Davide Girolami , Tommaso Tufarelli , Gerardo Adesso

In quantum mechanics, each conserved quantity (e.g., energy, position, linear momentum and angular momentum) is associated with a Hermitian operator. Its expected value can then be determined by performing a measurement on the wavefunction.…

Quantum state tomography serves as a key tool for identifying quantum states generated in quantum computers and simulators, typically involving local operations on individual particles or qubits to enable independent measurements. However,…

Quantum Gases · Physics 2026-03-26 Giacomo Marmorini , Takeshi Fukuhara , Daisuke Yamamoto

We present a theoretical framework to investigate spin chirality in molecular quantum systems. Focusing on a minimal three-spin-center model with antiferromagnetic exchange and symmetry breaking driven by an electric-field-induced…

Mesoscale and Nanoscale Physics · Physics 2025-04-25 Aman Ullah , Ziqi Hu , Juan Aragó , Alejandro Gaita-Ariño

A bipartite quantum system in a mixed state can exhibit nonclassical correlations, which can go beyond quantum entanglement. While quantum discord is the standard measure of quantifying such general quantum correlations, the nonclassicality…

Quantum Physics · Physics 2017-06-21 Amandeep Singh , Arvind , Kavita Dorai

We propose a new approach to the measurement of a single spin state, based on nuclear magnetic resonance (NMR) techniques and inspired by the coherent control over many-body systems envisaged by Quantum Information Processing (QIP). A…