Professor Timothy Ralph
Professor

Timothy Ralph

Email: 
Phone: 
+61 7 334 69693

Background

Professor Ralph obtained a BSc Hons from Macquarie University in 1989 and a PhD in Physics from The Australian National University in 1993. He has held three Australian Research Council Fellowships - Postdoctoral, QEII and Professorial. He is currently Node Director for the ARC Centre of Excellence for Quantum Computation and Communication Technology at the University of Queensland.

Availability

Professor Timothy Ralph is:
Available for supervision
Media expert

Fields of research

Physical Sciences

Qualifications

  • Bachelor (Honours) of Science (Advanced), Macquarie University
  • Doctor of Philosophy, Australian National University

Research interests

  • Linear Optics Quantum Computation.

    As part of the Centre for Quantum Computation and Communication Technology we are attempting to understand and implement simple quantum gates using the techniques of linear optics and measurement induced state projection.

  • Quantum Communication with Lasers.

    Quantum information techniques allow one to communicate with absolute security, amongst other applications. As part of the Centre for Quantum Computation and Communication Technology we are developing such secure communication protocols based on sending coherent states of light and measuring their amplitudes.

  • Relativistic Quantum Information.

    This project examines the interface between quantum mechanics, general relativity and information theory. It asks, both at a fundamental and practical level, what the ramifications for quantum information theory are when space-time curvature and rapid motion are introduced.

Search Professor Timothy Ralph’s works on UQ eSpace

430 works between 1991 and 2025
All (430) Journal Article (326) Book Chapter (7) Conference Publication (87) Book (2) Other Outputs (8)

161 - 180 of 430 works

2012

Journal Article

General relativistic effects in quantum interference of photons

Zych, Magdalena, Costa, Fabio, Pikovski, Igor, Ralph, Timothy C. and Brukner, Caslav (2012). General relativistic effects in quantum interference of photons. Classical and Quantum Gravity, 29 (22) 224010, 224010-1-224010-18. doi: 10.1088/0264-9381/29/22/224010

General relativistic effects in quantum interference of photons

2012

Journal Article

Quantum-enhanced optical-phase tracking

Yonezawa, Hidehiro, Nakane, Daisuke, Wheatley, Trevor A., Iwasawa, Kohjiro, Takeda, Shuntaro, Arao, Hajime, Ohki, Kentaro, Tsumura, Koji, Berry, Dominic W., Ralph, Timothy C., Wiseman, Howard M., Huntington, Elanor H. and Furusawa, Akira (2012). Quantum-enhanced optical-phase tracking. Science, 337 (6101), 1514-1517. doi: 10.1126/science.1225258

Quantum-enhanced optical-phase tracking

2012

Journal Article

Observing the operational significance of discord consumption

Gu, Mile, Chrzanowski, Helen M., Assad, Syed M., Symul, Thomas, Modi, Kavan, Ralph, Timothy C., Vedral, Vlatko and Lam, Ping Koy (2012). Observing the operational significance of discord consumption. Nature Physics, 8 (9), 671-675. doi: 10.1038/NPHYS2376

Observing the operational significance of discord consumption

2012

Journal Article

Continuous-variable quantum key distribution using thermal states

Weedbrook, Christian, Pirandola, Stefano and Ralph, Timothy C. (2012). Continuous-variable quantum key distribution using thermal states. Physical Review A, 86 (2) 022318, 022318.1-022318.12. doi: 10.1103/PhysRevA.86.022318

Continuous-variable quantum key distribution using thermal states

2012

Journal Article

Entanglement dynamics and quasi-periodicity in discrete quantum walks

Rohde, Peter P., Fedrizzi, Alessandro and Ralph, Timothy C. (2012). Entanglement dynamics and quasi-periodicity in discrete quantum walks. Journal of Modern Optics, 59 (8), 710-720. doi: 10.1080/09500340.2012.660204

Entanglement dynamics and quasi-periodicity in discrete quantum walks

2012

Journal Article

Gaussian quantum information

Weedbrook, Christian, Pirandola, Stefano, Garcia-Patron, Raul, Cerf, Nicolas J., Ralph, Timothy C., Shapiro, Jeffrey H. and Lloyd, Seth (2012). Gaussian quantum information. Reviews of Modern Physics, 84 (2), 621-669. doi: 10.1103/RevModPhys.84.621

Gaussian quantum information

2012

Journal Article

Error tolerance of the boson-sampling model for linear optics quantum computing

Rohde, Peter P. and Ralph, Timothy C. (2012). Error tolerance of the boson-sampling model for linear optics quantum computing. Physical Review A, 85 (2) 022332, 022332.1-022332.5. doi: 10.1103/PhysRevA.85.022332

Error tolerance of the boson-sampling model for linear optics quantum computing

2012

Journal Article

Extraction of timelike entanglement from the quantum vacuum

Olson, S. Jay and Ralph, Timothy C. (2012). Extraction of timelike entanglement from the quantum vacuum. Physical Review A, 85 (1) 012306, 012306-1-012306-7. doi: 10.1103/PhysRevA.85.012306

Extraction of timelike entanglement from the quantum vacuum

2012

Journal Article

Relativistic quantum information and time machines

Ralph, Timothy C. and Downes, Tony G. (2012). Relativistic quantum information and time machines. Contemporary Physics, 53 (1), 1-16. doi: 10.1080/00107514.2011.640146

Relativistic quantum information and time machines

2011

Journal Article

Quantum fields on closed timelike curves

Pienaar, J.L., Myers, C.R. and Ralph, T.C. (2011). Quantum fields on closed timelike curves. Physical Review A: Atomic, molecular and optical physics, 84 (6) 062316, 062316. doi: 10.1103/PhysRevA.84.062316

Quantum fields on closed timelike curves

2011

Conference Publication

Continuous variable quantum key distribution: Security, repeaters and relativity

Walk, Nathan, Ralph, Timothy C., Downes, Tony, Symul, Thomas and Lam, Ping Koy (2011). Continuous variable quantum key distribution: Security, repeaters and relativity. Washington, D.C.: Optical Society of America (OSA). doi: 10.1364/icqi.2011.qmf4

Continuous variable quantum key distribution: Security, repeaters and relativity

2011

Journal Article

Photon-number discrimination without a photon counter and its application to reconstructing non-Gaussian states

Chrzanowski, H. M., Bernu, J., Sparkes, B. M., Hage, B., Lund, A. P., Ralph, T. C., Lam, P. K. and Symul, T. (2011). Photon-number discrimination without a photon counter and its application to reconstructing non-Gaussian states. Physical Review A (Atomic, Molecular and Optical Physics), 84 (5) 050302, 050302.1-050302.4. doi: 10.1103/PhysRevA.84.050302

Photon-number discrimination without a photon counter and its application to reconstructing non-Gaussian states

2011

Journal Article

Coherent state topological cluster state production

Myers, C. R. and Ralph, T. C. (2011). Coherent state topological cluster state production. New Journal of Physics, 13 (11) 115015, 1-24. doi: 10.1088/1367-2630/13/11/115015

Coherent state topological cluster state production

2011

Journal Article

Reply to "Comment on 'Information flow of quantum states interacting with closed timelike curves"

Ralph, T.C. and Myers, C.R. (2011). Reply to "Comment on 'Information flow of quantum states interacting with closed timelike curves". Physical Review A, 84 (5) 056302, 056302-1-056302-2. doi: 10.1103/PhysRevA.84.056302

Reply to "Comment on 'Information flow of quantum states interacting with closed timelike curves"

2011

Journal Article

Quantum error correction of continuous-variable states against Gaussian noise

Ralph, T. C. (2011). Quantum error correction of continuous-variable states against Gaussian noise. Physical Review A, 84 (2) 022339, 022339-1-022339-4. doi: 10.1103/PhysRevA.84.022339

Quantum error correction of continuous-variable states against Gaussian noise

2011

Journal Article

Adding control to arbitrary unknown quantum operations

Zhou, Xiao-Qi, Ralph, Timothy C., Kalasuwan, Pruet, Zhang, Mian, Peruzzo, Alberto, Lanyon, Benjamin P. and O'Brien, Jeremy L. (2011). Adding control to arbitrary unknown quantum operations. Nature Communications, 2 (1 Article # 413) 413. doi: 10.1038/ncomms1392

Adding control to arbitrary unknown quantum operations

2011

Journal Article

Space-time qubits

Pienaar, J. L., Myers, C. R. and Ralph, T. C. (2011). Space-time qubits. Physical Review A, 84 (2) 022315. doi: 10.1103/PhysRevA.84.022315

Space-time qubits

2011

Journal Article

Entangling moving cavities in noninertial frames

Downes, T. G., Fuentes, I. and Ralph, T. C. (2011). Entangling moving cavities in noninertial frames. Physical Review Letters, 106 (21) 210502, 210502.1-210502.4. doi: 10.1103/PhysRevLett.106.210502

Entangling moving cavities in noninertial frames

2011

Journal Article

Time-resolved detection and mode mismatch in a linear optics quantum gate

Rohde, Peter P. and Ralph, Timothy C. (2011). Time-resolved detection and mode mismatch in a linear optics quantum gate. New Journal of Physics, 13 (5) 053036, 053036. doi: 10.1088/1367-2630/13/5/053036

Time-resolved detection and mode mismatch in a linear optics quantum gate

2011

Journal Article

Entanglement between the future and the past in the quantum vacuum

Olson, S. Jay and Ralph, Timothy C. (2011). Entanglement between the future and the past in the quantum vacuum. Physical Review Letters, 106 (11) 110404, 110404.1-110404.4. doi: 10.1103/PhysRevLett.106.110404

Entanglement between the future and the past in the quantum vacuum

Current funding

  • 2024 - 2027
    Deployable Quantum Relay (DSP Multi-Party Collaborative Project led by Griffith University)
    Commonwealth Defence Science and Technology Group
    Open grant
  • 2023 - 2025
    Quantum Communications with Continuous Variables (UNSW subcontract agreement)
    University of New South Wales
    Open grant
  • 2018 - 2025
    ARC Centre of Excellence for Quantum Computation and Communication Technology (CQC2T) (ARC Centre of Excellence administered by UNSW)
    University of New South Wales
    Open grant

Past funding

  • 2021 - 2024
    A Space-Based Quantum Communications Platform using Continuous Variables (ARC Linkage Project led by University of NSW)
    University of New South Wales
    Open grant
  • 2019 - 2021
    Enabling quantum information technology with 60 photons and beyond
    United States Asian Office of Aerospace Research and Development
    Open grant
  • 2019 - 2020
    Platform independent studies on optimising quantum repeater architectures (Australian Department of Defence grant administered by QuintessenceLabs Pty Ltd)
    Quintessencelabs Pty Ltd
    Open grant
  • 2017 - 2020
    Quantum Key Distribution (QKD) System
    Quintessencelabs Pty Ltd
    Open grant
  • 2011 - 2018
    ARC Centre of Excellence for Quantum Computation and Communication Technology (ARC COE administered by the University of New South Wales)
    University of New South Wales
    Open grant
  • 2011 - 2013
    Quantum Optics and Quantum Information
    Vice-Chancellor's Senior Research Fellowship
    Open grant
  • 2010
    Quantum memory
    Australian National University
    Open grant
  • 2008 - 2012
    Quantum repeater technologies for continuous variable (ARC Discovery Project DP0879277 administered by ANU)
    Australian National University
    Open grant
  • 2006 - 2010
    Optical Quantum Computation
    ARC Discovery Projects
    Open grant
  • 2003 - 2010
    ARC Centre of Excellence for Quantum Computer Technology (UNSW lead institution)
    ARC Centres of Excellence
    Open grant
  • 2003 - 2005
    Quantum Photonics- Travel Award
    Australian National University
    Open grant
  • 2002 - 2004
    Towards Quantum Computation with Light
    UQ Foundation Research Excellence Awards - DVC(R) Funding
    Open grant
  • 2002 - 2004
    ARC Discovery Project - Quantum Photonics with continuous laser beams
    Australian National University
    Open grant
  • 2001 - 2004
    Experimental Implementation of Efficient Linear Optics Quantum Computation
    United States Army Research Office
    Open grant
  • 2000
    Optical entangler for Quantum Communication
    Australian National University
    Open grant
  • 2000 - 2005
    Quantum Information with Continuous Variables
    ARC Australian Research Fellowship/QEII F/ship
    Open grant
  • 2000
    Quantum information with continuous variables
    UQ New Staff Research Start-Up Fund
    Open grant

Availability

Professor Timothy Ralph is:
Available for supervision

Before you email them, read our advice on how to contact a supervisor.

Available projects

  • Optical Quantum Computation

    As part of the Centre for Quantum Computation and Communication Technology we are attempting to understand and implement optical quantum computation using the techniques of linear optic networks and measurement induced state projection. Projects are available examining intemediate scale protocols and algorithms as well as large scale architectures.

  • Quantum communication with lasers

    Quantum information techniques allow one to communicate with absolute security, amongst other applications. As part of the Centre for Quantum Computation and Communication Technology we are developing such secure communication protocols based on sending coherent and squeezed states of light and measuring their amplitudes. Projects concerning quantum repeaters for extending communication links and satellite to ground quantum communication are available.

  • Relativistic quantum information

    Projects are available that involve examining the interface between quantum mechanics, general relativity and information theory. They ask, both at a fundamental and practical level, what the ramifications for quantum information theory are when space-time curvature, rapid motion and/or very fast transformations are introduced.

Supervision history

Current supervision

  • Doctor Philosophy

    Practical applications of quantum sampling algorithms

    Principal Advisor

  • Master Philosophy

    Quantum effects in general relativistic spacetimes

    Principal Advisor

  • Doctor Philosophy

    Production of quantum communication systems capable of operating onboard low-earth orbit satellites and developing integrated quantum and classical satellite communication protocols.

    Principal Advisor

  • Master Philosophy

    Resolving paradoxes of closed timelike curves

    Principal Advisor

  • Doctor Philosophy

    Quantum mechanics near closed timelike curves

    Principal Advisor

  • Doctor Philosophy

    Beyond quantum field theory on a curved background

    Principal Advisor

  • Doctor Philosophy

    Production of quantum communication systems capable of operating onboard low-earth orbit satellites and developing integrated quantum and classical satellite communication protocols.

    Principal Advisor

  • Doctor Philosophy

    Demonstration of relativistic Bohmian trajectories of photons

    Associate Advisor

    Other advisors: Dr Daniel Peace, Associate Professor Jacqui Romero

  • Doctor Philosophy

    Thermodynamic fluctuation relations for gravitating quantum systems

    Associate Advisor

    Other advisors: Dr Carolyn Wood, Dr Laura Henderson

  • Doctor Philosophy

    Perspectives on the de Broglie-Bohm interpretation

    Associate Advisor

    Other advisors: Associate Professor Sally Shrapnel, Dr Peter Evans

Completed supervision

Enquiries

Contact Professor Timothy Ralph directly for media enquiries about:

  • Laser noise - physics
  • Optics - quantum
  • Physics
  • Quantum information
  • Quantum key distribution with continuous variables
  • Quantum optics
  • Quantum physics
  • Teleportation

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