Topological state permutations in time-modulated non-Hermitian multiqubit systems with suppressed nonadiabatic transitions

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F25%3A73631706" target="_blank" >RIV/61989592:15310/25:73631706 - isvavai.cz</a>

Výsledek na webu

<a href="https://journals.aps.org/prresearch/pdf/10.1103/m17d-whsf" target="_blank" >https://journals.aps.org/prresearch/pdf/10.1103/m17d-whsf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/m17d-whsf" target="_blank" >10.1103/m17d-whsf</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Topological state permutations in time-modulated non-Hermitian multiqubit systems with suppressed nonadiabatic transitions

Popis výsledku v původním jazyce

Non-Hermitian systems have been at the center of intense research for over a decade, partly due to their nontrivial energy topology formed by intersecting Riemann manifolds with branch points known as exceptional points (EPs). This spectral property can be exploited, e.g., to achieve topologically controlled state permutations that are necessary for implementing a wide class of classical and quantum information protocols. However, the complex-valued spectra of typical non-Hermitian systems lead to instabilities, losses, and breakdown of adiabaticity, which impedes the practical useof EP-induced energy topologies in quantum information protocols based on state permutation symmetries. Indeed, in a given non-Hermitian multiqubit system, the dynamicalwinding around EPs always results in a predetermined set of attenuated final eigenstates, due to the interplay of decoherence and nonadiabatic transitions, irrespective of the initial conditions. In this work, we address this long-standing problem by introducing a model of interacting qubits governed by an effective non-Hermitian Hamiltonian that hosts a special type of EPs while maintaining a completely real energy spectrum, ensuring the absence of losses in the system’s dynamics. We demonstrate that such non-Hermitian Hamiltonians enable the realization of genuine, in general, non-Abelian permutation groups in the multiqubit system’s eigenspace while dynamically encircling these EPs. Our findings indicate that, contrary to previous beliefs, non-Hermiticity can be utilized to achieve controlled topological state permutations in time-modulated multiqubit systems, thus paving the way for the advancement and development of quantum information protocols in real-world non-Hermitian quantum systems

Název v anglickém jazyce

Topological state permutations in time-modulated non-Hermitian multiqubit systems with suppressed nonadiabatic transitions

Popis výsledku anglicky

Non-Hermitian systems have been at the center of intense research for over a decade, partly due to their nontrivial energy topology formed by intersecting Riemann manifolds with branch points known as exceptional points (EPs). This spectral property can be exploited, e.g., to achieve topologically controlled state permutations that are necessary for implementing a wide class of classical and quantum information protocols. However, the complex-valued spectra of typical non-Hermitian systems lead to instabilities, losses, and breakdown of adiabaticity, which impedes the practical useof EP-induced energy topologies in quantum information protocols based on state permutation symmetries. Indeed, in a given non-Hermitian multiqubit system, the dynamicalwinding around EPs always results in a predetermined set of attenuated final eigenstates, due to the interplay of decoherence and nonadiabatic transitions, irrespective of the initial conditions. In this work, we address this long-standing problem by introducing a model of interacting qubits governed by an effective non-Hermitian Hamiltonian that hosts a special type of EPs while maintaining a completely real energy spectrum, ensuring the absence of losses in the system’s dynamics. We demonstrate that such non-Hermitian Hamiltonians enable the realization of genuine, in general, non-Abelian permutation groups in the multiqubit system’s eigenspace while dynamically encircling these EPs. Our findings indicate that, contrary to previous beliefs, non-Hermiticity can be utilized to achieve controlled topological state permutations in time-modulated multiqubit systems, thus paving the way for the advancement and development of quantum information protocols in real-world non-Hermitian quantum systems

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10306 - Optics (including laser optics and quantum optics)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review Research

ISSN

2643-1564

e-ISSN

2643-1564

Svazek periodika

7

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

22

Strana od-do

"033242-1"-"033242-22"

Kód UT WoS článku

001569599500003

EID výsledku v databázi Scopus

2-s2.0-105024982306