Quantum circuits to measure scalar spin chirality

Autor: L. I. Reascos, Bruno Murta, E. F. Galvão, J. Fernández-Rossier
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Physical Review Research, Vol 5, Iss 4, p 043087 (2023)
Druh dokumentu: article
ISSN: 2643-1564
DOI: 10.1103/PhysRevResearch.5.043087
Popis: The scalar spin chirality is a three-body physical observable that plays an outstanding role both in classical magnetism, characterizing non-co-planar spin textures, and in quantum magnetism, as an order parameter for chiral spin liquids. In quantum information, the scalar spin chirality is a witness of genuine tripartite entanglement. Here we propose an indirect measurement scheme, based on the Hadamard test, to estimate the scalar spin chirality for general quantum states. We apply our method to study chirality in two types of quantum states: generic one-magnon states of a ferromagnet, and the ground state of a model with competing symmetric and antisymmetric exchange. We show a single-shot determination of the scalar chirality is possible for chirality eigenstates, via quantum phase estimation with a single auxiliary qutrit. Our approach provides a unified theory of chirality in classical and quantum magnetism.
Databáze: Directory of Open Access Journals