mateltechИзвестия высших учебных заведений. Материалы электронной техникиIzvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering1609-35772413-6387MISIS10.17073/1609-3577j.met202312.570mateltech-570Research ArticleФизические свойства и методы исследованияPHYSICAL CHARACTERISTICS AND THEIR STUDYМоделирование квантовой динамики фрустрированных сетей джозефсоновских контактовModeling of the quantum dynamics of frustrated networks of Josephson junctionshttps://orcid.org/0009-0000-3931-1058БурцевП. С.BurtsevP. S.

Ленинский просп., д. 4, стр. 1, Москва, 119049

Бурцев Павел Сергеевич — лаборант-исследователь, магистр направления "Квантовое материаловедение", дизайн-центр квантового проектирования

4-1 Leninsky Ave., Moscow 119049

Pavel S. Burtsev — Laboratory Research Assistant, Master's Degree, Quantum Design Center

ps.burtsev@misis.ruhttps://orcid.org/0009-0001-3736-3687МигдисовР. А.MigdisovR. A.

Ленинский просп., д. 4, стр. 1, Москва, 119049

Мигдисов Роман Александрович — лаборант-исследователь, магистр направления "Квантовое материаловедение", дизайн-центр квантового проектирования

4-1 Leninsky Ave., Moscow 119049

Roman A. Migdisov — Laboratory Research Assistant, Master's Degree, Quantum Design Center

m1910570@edu.misis.ruhttps://orcid.org/0000-0002-1142-2626МалееваН. А.MaleevaN. A.

Ленинский просп., д. 4, стр. 1, Москва, 119049

Малеева Наталия Андреевна — старший научный сотрудник, лаборатория криоэлектронных систем

4-1 Leninsky Ave., Moscow 119049

Nataliya A. Maleeva — Cand. Sci. (Phys.-Math.), Senior Researcher, Laboratory for Cryoelectrinic Systems

n.maleeva@misis.ruhttps://orcid.org/0000-0002-0265-2534ФистульМ. В.FistulM. V.

Ленинский просп., д. 4, стр. 1, Москва, 119049

Фистуль Михаил Викторович — ведущий научный сотрудник, лаборатория сверхпроводниковых квантовых технологий

4-1 Leninsky Ave., Moscow 119049

Mikhail V. Fistul — Cand. Sci. (Phys.-Math.), Leading Researcher, Laboratory of Superconducting Quantum Technologies

fistul@tp3.rub.deНациональный исследовательский технологический университет «МИСИС»РоссияNational University of Science and Technology “MISIS”Russian Federation202407052024272154164Copyright © Бурцев П.С., Мигдисов Р.А., Малеева Н.А., Фистуль М.В., 20242024Бурцев П.С., Мигдисов Р.А., Малеева Н.А., Фистуль М.В.Burtsev P.S., Migdisov R.A., Maleeva N.A., Fistul M.V.This work is licensed under a Creative Commons Attribution 4.0 License.https://met.misis.ru/jour/article/view/570

Теоретически исследована макроскопическая квантовая динамика в фрустрированных сетях взаимодействующих джозефсоновских контактов (ф-СДК). Рассмотрено два типа ф-СДК: квазиодномерная пилообразные цепочка и двумерная кагомэ решетка малых (квантовых) джозефсоновских контактов. Фрустрация в системе вводится с помощью периодически расположенных 0- и p-джозефсоновских контактов. В фрустрированном режиме спонтанные вихревые токи двух противоположных направлений протекают в каждом базовом элементе ф-СДК, состоящего из трех сверхпроводящих островов, соединенных джозефсоновскими контактами. Коллективная квантовая динамика вихревых токов описывается эффективным гамильтонианом взаимодействующих спинов, в котором были учтены и квантовая суперпозиция вихревых токов в отдельном базовом элементе и дальнодействующее взаимодействие между вихревыми токами. Обсуждаются два типа взаимодействия: зарядовое взаимодействие между сверхпроводящими островами в пилообразных цепочках и топологические ограничения в решетке кагомэ. Показано, что дальнодействующее взаимодействие спинов в этих ф-СДК позволяет реализовать различные коллективные квантовые фазы с большой квантовой запутанностью. Предполагается, что ф-СДК могут стать перспективной платформой для моделирования сложных сильно коррелированных электронных твердотельных, молекулярных и биологических систем, а также магнитных систем с фрустрацией.

We report a theoretical study of the macroscopic quantum dynamics in frustrated networks of interacting Josephson junctions (f-NJJs). We consider two exemplary types of f-NJJs: quasi-1D sawtooth arrays and 2D Kagome lattice of small (quantum) Josephson junctions. The frustration is provided by periodically arranged 0- and π-Josephson junctions. In the frustration regime the clockwise (anticlockwise) persistent currents penetrate each basic cell, i.e., three superconducting islands connected by Josephson junctions. Collective quantum dynamics of persistent currents is described by the effective interacting spins Hamiltonian where we take into account the quantum superposition of persistent currents in a single cell induced by the macroscopic quantum tunneling of Josephson phases and a long- range interaction between persistent currents. Two types of interaction are discussed: charge interaction between superconducting islands in sawtooth arrays and topological constraints in Kagome lattice. We demonstrate that the long-interaction between spins in these f-NJJs allows one to realize the various collective quantum phases with a large quantum entanglement. We anticipate that f-NJJs can be a perspective platform for modeling complex strongly correlated electronic solid state, molecular, and biological systems, as well as frustrated magnetic systems.

джозефсоновские контактыфрустрированные сверпроводящие сетирешетка кагомэпотоковый кубитквантовая запутанностьJosephson junctionsfrustrated superconducting networksKagome latticeflux qubitquantum entanglementИсследование выполнено при финансовой поддержке Российского научного фонда (проект № 21-72-30026, https://rscf.ru/en/project/21-72-30026/).The study was carried out with financial support from the Russian Science Foundation (project No. 21-72-30026, https://rscf.ru/en/project/21-72-30026/).ReferencesBeloborodov I.S., Efetov K.B., Lopatin A.V., Vinokur V.M. Granular electronic systems. Reviews of Modern Physics. 2007; 79(2): 469. https://doi.org/10.1103/RevModPhys.79.469Beloborodov I.S., Efetov K.B., Lopatin A.V., Vinokur V.M. Granular electronic systems. Reviews of Modern Physics. 2007; 79(2): 469. https://doi.org/10.1103/RevModPhys.79.469van der Zant H.S.J., Elion W.J., Geerligs L.J., Mooij J.E. 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The authors declare that there are no conflicts of interest present.