Effect of interatomic repulsion and quasi-degenerate states on a Kitaev-transmon qubit based on double quantum dots

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Palacios, Clara, Aligia, Armando A.
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866915762852069376
author Palacios, Clara
Aligia, Armando A.
author_facet Palacios, Clara
Aligia, Armando A.
contents We investigate the effect of interatomic Coulomb repulsion $V$ and particular states disregarded previously on the Kitaev-transmon system proposed by Pino \textit{et al.} \cite{pino} which consists of a Josephson junction between two double quantum dots (DQDs) modeled by the spinless Kitaev Hamiltonian. For an isolated DQD, we demonstrate that a ``sweet spot'' hosting ``poor man's Majorana'' states persist in the presence of $V$, provided that system parameters are appropriately tuned. For the full system, we demonstrate that at the sweet spots of both DQDs, all eigenstates are doubly degenerate. This degeneracy arises from the existence of an operator that maps between two decoupled Hilbert subspaces. Away from the sweet spots, the microwave spectrum becomes sensitive to the choice of initial state. In our study, we consider transitions from the ground state (which depending on the flux alternates between the above mentioned subspaces) to all possible excited states. This scenario corresponds to a system initially in thermal equilibrium at low temperature.
format Preprint
id arxiv_https___arxiv_org_abs_2505_01610
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Effect of interatomic repulsion and quasi-degenerate states on a Kitaev-transmon qubit based on double quantum dots
Palacios, Clara
Aligia, Armando A.
Mesoscale and Nanoscale Physics
Strongly Correlated Electrons
We investigate the effect of interatomic Coulomb repulsion $V$ and particular states disregarded previously on the Kitaev-transmon system proposed by Pino \textit{et al.} \cite{pino} which consists of a Josephson junction between two double quantum dots (DQDs) modeled by the spinless Kitaev Hamiltonian. For an isolated DQD, we demonstrate that a ``sweet spot'' hosting ``poor man's Majorana'' states persist in the presence of $V$, provided that system parameters are appropriately tuned. For the full system, we demonstrate that at the sweet spots of both DQDs, all eigenstates are doubly degenerate. This degeneracy arises from the existence of an operator that maps between two decoupled Hilbert subspaces. Away from the sweet spots, the microwave spectrum becomes sensitive to the choice of initial state. In our study, we consider transitions from the ground state (which depending on the flux alternates between the above mentioned subspaces) to all possible excited states. This scenario corresponds to a system initially in thermal equilibrium at low temperature.
title Effect of interatomic repulsion and quasi-degenerate states on a Kitaev-transmon qubit based on double quantum dots
topic Mesoscale and Nanoscale Physics
Strongly Correlated Electrons
url https://arxiv.org/abs/2505.01610