---
OA_place: repository
_id: '19533'
abstract:
- lang: eng
  text: "This thesis explores advancements in quantum remote sensing and non-equilibrium
    phase\r\ntransitions in the microwave regime, with a focus on dissipative phase
    transitions and quantumenhanced sensing.\r\nIn the first project, I experimentally
    studied photon blockade breakdown as a dissipative phase\r\ntransition in a zero-dimensional
    cavity-qubit system. By defining an appropriate thermodynamic\r\nlimit, we demonstrated
    that the observed bistability is a genuine signature of a first-order\r\nphase
    transition in this system. This work provides insight into non-equilibrium quantum\r\ndynamics
    and phase transitions in driven-dissipative open quantum systems.\r\nThe second
    project focuses on the experimental realization of a phase-conjugate receiver
    for\r\nquantum illumination (QI), a quantum sensing protocol that enhances target
    detection in noisy\r\nenvironments using entangled light. While an ideal spontaneous
    parametric down-conversion\r\n(SPDC) source and receiver could, in theory, provide
    up to a 6 dB advantage over classical\r\nillumination, no such ideal receiver
    exists. Instead, we explore an experimental realization of a\r\nphase-conjugate
    receiver for QI in the microwave regime at millikelvin temperatures using a\r\nJosephson
    parametric converter (JPC) as a source of continuous-variable Gaussian entangled\r\nsignal-idler
    pairs, where a maximum 3 dB advantage is theoretically achievable. We investigate\r\nkey
    experimental limitations that constrain practical QI performance, contributing
    to the\r\ndevelopment of quantum-enhanced sensing.\r\nAdditionally, this thesis
    presents efficient digital signal processing (DSP) techniques implemented in C++
    and Python in collaboration with Przemysław Zieliński and Luka Drmić. These\r\nmethods,
    optimized using the Intel Integrated Performance Primitives (IPP) library, have
    been\r\nessential in data acquisition, noise filtering, and correlation analysis
    across multiple research\r\nprojects. Although not real-time, these DSP techniques
    significantly enhance the accuracy of\r\nquantum measurements.\r\nOverall, this
    thesis advances quantum-enhanced sensing by establishing the thermodynamic\r\nlimit
    in a single transmon-cavity system and experimentally exploring a phase-conjugate
    receiver\r\nfor QI. These findings contribute to quantum metrology, particularly
    for weak signal detection\r\nand remote sensing in noisy environments.\r\n"
acknowledged_ssus:
- _id: ScienComp
- _id: M-Shop
- _id: NanoFab
- _id: LifeSc
- _id: SSU
acknowledgement: "I acknowledge the generous financial support of the Austrian Science
  Fund (FWF) via BeyondC\r\n(F7105) and the European Union’s Horizon 2020 research
  and innovation program (FETopen\r\nQUARTET, Grant Agreement No. 862644), which made
  this research possible. I also extend\r\nmy sincere appreciation to the MIBA workshop
  and the Institute of Science and Technology\r\nAustria nanofabrication facility
  for their technical assistance, which was instrumental in realizing\r\nthis work."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Riya
  full_name: Sett, Riya
  id: 2E6D040E-F248-11E8-B48F-1D18A9856A87
  last_name: Sett
  orcid: 0000-0001-7641-8348
citation:
  ama: Sett R.  Quantum remote sensing and non-equilibrium phase transitions in the
    microwave regime. 2025. doi:<a href="https://doi.org/10.15479/AT-ISTA-19533">10.15479/AT-ISTA-19533</a>
  apa: Sett, R. (2025). <i> Quantum remote sensing and non-equilibrium phase transitions
    in the microwave regime</i>. Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/AT-ISTA-19533">https://doi.org/10.15479/AT-ISTA-19533</a>
  chicago: Sett, Riya. “ Quantum Remote Sensing and Non-Equilibrium Phase Transitions
    in the Microwave Regime.” Institute of Science and Technology Austria, 2025. <a
    href="https://doi.org/10.15479/AT-ISTA-19533">https://doi.org/10.15479/AT-ISTA-19533</a>.
  ieee: R. Sett, “ Quantum remote sensing and non-equilibrium phase transitions in
    the microwave regime,” Institute of Science and Technology Austria, 2025.
  ista: Sett R. 2025.  Quantum remote sensing and non-equilibrium phase transitions
    in the microwave regime. Institute of Science and Technology Austria.
  mla: Sett, Riya. <i> Quantum Remote Sensing and Non-Equilibrium Phase Transitions
    in the Microwave Regime</i>. Institute of Science and Technology Austria, 2025,
    doi:<a href="https://doi.org/10.15479/AT-ISTA-19533">10.15479/AT-ISTA-19533</a>.
  short: R. Sett,  Quantum Remote Sensing and Non-Equilibrium Phase Transitions in
    the Microwave Regime, Institute of Science and Technology Austria, 2025.
corr_author: '1'
date_created: 2025-04-09T16:44:26Z
date_published: 2025-04-01T00:00:00Z
date_updated: 2026-01-30T10:12:59Z
day: '1'
ddc:
- '530'
degree_awarded: PhD
department:
- _id: GradSch
- _id: JoFi
doi: 10.15479/AT-ISTA-19533
ec_funded: 1
file:
- access_level: open_access
  checksum: ba6cd2289d0141a160a14fc97df1632f
  content_type: application/pdf
  creator: rsett
  date_created: 2025-04-10T11:33:22Z
  date_updated: 2025-10-11T22:30:02Z
  embargo: 2025-10-11
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  file_size: 4129208
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  creator: rsett
  date_created: 2025-04-10T11:34:08Z
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  file_id: '19539'
  file_name: PhD Thesis Riya Sett.zip
  file_size: 6646110
  relation: source_file
file_date_updated: 2025-10-11T22:30:02Z
has_accepted_license: '1'
keyword:
- phase transition
- open quantum system
- phase diagram
- cavity quantum electrodynamics
- superconducting qubits
- semiclassical physics
- quantum optics
- josephson junction
- parametric converter
- phase conjugation
- quantum radar
- quantum entanglement
- correlation
- quantum sensing
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '04'
oa: 1
oa_version: Published Version
page: '109'
project:
- _id: 237CBA6C-32DE-11EA-91FC-C7463DDC885E
  call_identifier: H2020
  grant_number: '862644'
  name: Quantum readout techniques and technologies
- _id: 26927A52-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: F07105
  name: Integrating superconducting quantum circuits
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '13117'
    relation: part_of_dissertation
    status: public
  - id: '18978'
    relation: research_data
    status: public
  - id: '17183'
    relation: part_of_dissertation
    status: public
  - id: '19280'
    relation: part_of_dissertation
    status: public
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: ' Quantum remote sensing and non-equilibrium phase transitions in the microwave
  regime'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2025'
...