---
OA_place: publisher
_id: '12366'
abstract:
- lang: eng
  text: "Recent substantial advances in the feld of superconducting circuits have
    shown its\r\npotential as a leading platform for future quantum computing. In
    contrast to classical\r\ncomputers based on bits that are represented by a single
    binary value, 0 or 1, quantum\r\nbits (or qubits) can be in a superposition of
    both. Thus, quantum computers can store\r\nand handle more information at the
    same time and a quantum advantage has already\r\nbeen demonstrated for two types
    of computational tasks. Rapid progress in academic\r\nand industry labs accelerates
    the development of superconducting processors which may\r\nsoon fnd applications
    in complex computations, chemical simulations, cryptography, and\r\noptimization.
    Now that these machines are scaled up to tackle such problems the questions\r\nof
    qubit interconnects and networks becomes very relevant. How to route signals on-chip\r\nbetween
    diferent processor components? What is the most efcient way to entangle\r\nqubits?
    And how to then send and process entangled signals between distant cryostats\r\nhosting
    superconducting processors?\r\nIn this thesis, we are looking for solutions to
    these problems by studying the collective\r\nbehavior of superconducting qubit
    ensembles. We frst demonstrate on-demand tunable\r\ndirectional scattering of
    microwave photons from a pair of qubits in a waveguide. Such a\r\ndevice can route
    microwave photons on-chip with a high diode efciency. Then we focus\r\non studying
    ultra-strong coupling regimes between light (microwave photons) and matter\r\n(superconducting
    qubits), a regime that could be promising for extremely fast multi-qubit\r\nentanglement
    generation. Finally, we show coherent pulse storage and periodic revivals\r\nin
    a fve qubit ensemble strongly coupled to a resonator. Such a reconfgurable storage\r\ndevice
    could be used as part of a quantum repeater that is needed for longer-distance\r\nquantum
    communication.\r\nThe achieved high degree of control over multi-qubit ensembles
    highlights not only the\r\nbeautiful physics of circuit quantum electrodynamics,
    it also represents the frst step\r\ntoward new quantum simulation and communication
    methods, and certain techniques\r\nmay also fnd applications in future superconducting
    quantum computing hardware.\r\n"
acknowledged_ssus:
- _id: NanoFab
- _id: M-Shop
- _id: EM-Fac
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Elena
  full_name: Redchenko, Elena
  id: 2C21D6E8-F248-11E8-B48F-1D18A9856A87
  last_name: Redchenko
citation:
  ama: Redchenko E. Controllable states of superconducting Qubit ensembles. 2022.
    doi:<a href="https://doi.org/10.15479/at:ista:12132">10.15479/at:ista:12132</a>
  apa: Redchenko, E. (2022). <i>Controllable states of superconducting Qubit ensembles</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:12132">https://doi.org/10.15479/at:ista:12132</a>
  chicago: Redchenko, Elena. “Controllable States of Superconducting Qubit Ensembles.”
    Institute of Science and Technology Austria, 2022. <a href="https://doi.org/10.15479/at:ista:12132">https://doi.org/10.15479/at:ista:12132</a>.
  ieee: E. Redchenko, “Controllable states of superconducting Qubit ensembles,” Institute
    of Science and Technology Austria, 2022.
  ista: Redchenko E. 2022. Controllable states of superconducting Qubit ensembles.
    Institute of Science and Technology Austria.
  mla: Redchenko, Elena. <i>Controllable States of Superconducting Qubit Ensembles</i>.
    Institute of Science and Technology Austria, 2022, doi:<a href="https://doi.org/10.15479/at:ista:12132">10.15479/at:ista:12132</a>.
  short: E. Redchenko, Controllable States of Superconducting Qubit Ensembles, Institute
    of Science and Technology Austria, 2022.
corr_author: '1'
date_created: 2023-01-25T09:17:02Z
date_published: 2022-09-26T00:00:00Z
date_updated: 2026-04-07T14:22:39Z
day: '26'
ddc:
- '530'
degree_awarded: PhD
department:
- _id: GradSch
- _id: JoFi
doi: 10.15479/at:ista:12132
ec_funded: 1
file:
- access_level: open_access
  checksum: 39eabb1e006b41335f17f3b29af09648
  content_type: application/pdf
  creator: cchlebak
  date_created: 2023-01-25T09:41:49Z
  date_updated: 2023-01-26T23:30:44Z
  embargo: 2022-12-28
  file_id: '12367'
  file_name: Final_Thesis_ES_Redchenko.pdf
  file_size: 56076868
  relation: main_file
file_date_updated: 2023-01-26T23:30:44Z
has_accepted_license: '1'
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
page: '168'
project:
- _id: 2564DBCA-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '665385'
  name: International IST Doctoral Program
- _id: 26336814-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '758053'
  name: A Fiber Optic Transceiver for Superconducting Qubits
- _id: 237CBA6C-32DE-11EA-91FC-C7463DDC885E
  call_identifier: H2020
  grant_number: '862644'
  name: Quantum readout techniques and technologies
publication_identifier:
  isbn:
  - 978-3-99078-024-4
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
status: public
supervisor:
- first_name: Johannes M
  full_name: Fink, Johannes M
  id: 4B591CBA-F248-11E8-B48F-1D18A9856A87
  last_name: Fink
  orcid: 0000-0001-8112-028X
title: Controllable states of superconducting Qubit ensembles
type: dissertation
user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd
year: '2022'
...