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

429 works between 1991 and 2025
All (429) Journal Article (325) Book Chapter (7) Conference Publication (87) Book (2) Other Outputs (8)

121 - 140 of 429 works

2014

Journal Article

Measurement-based noiseless linear amplification for quantum communication

Chrzanowski, Helen M., Walk, Nathan, Assad, Syed M., Janousek, Jiri, Hosseini, Sara, Ralph, Timothy C., Symul, Thomas and Lam, Ping Koy (2014). Measurement-based noiseless linear amplification for quantum communication. Nature Photonics, 8 (4), 333-338. doi: 10.1038/nphoton.2014.49

Measurement-based noiseless linear amplification for quantum communication

2014

Journal Article

Optimal architecture for a nondeterministic noiseless linear amplifier

McMahon, N. A., Lund, A. P. and Ralph, T. C. (2014). Optimal architecture for a nondeterministic noiseless linear amplifier. Physical Review A, 89 (2) 023846. doi: 10.1103/PhysRevA.89.023846

Optimal architecture for a nondeterministic noiseless linear amplifier

2014

Journal Article

Experimental verification of quantum discord in continuous-variable states

Hosseini, S., Rahimi-Keshari, S., Haw, J. Y., Assad, S. M., Chrzanowski, H. M., Janousek, J., Symul, T., Ralph, T. C. and Lam, P. K. (2014). Experimental verification of quantum discord in continuous-variable states. Journal of Physics B: Atomic, Molecular and Optical Physics, 47 (2) 025503, 025503. doi: 10.1088/0953-4075/47/2/025503

Experimental verification of quantum discord in continuous-variable states

2014

Journal Article

Generation of hybrid entanglement of light

Jeong, Hyunseok, Zavatta, Alessandro, Kang, Minsu, Lee, Seung-Woo, Costanzo, Lucas S., Grandi, Samuele, Ralph, Timothy C. and Bellini, Marco (2014). Generation of hybrid entanglement of light. Nature Photonics, 8 (7), 564-569. doi: 10.1038/nphoton.2014.136

Generation of hybrid entanglement of light

2014

Conference Publication

Entanglement and simplified quantum information operations

Patel, Raj B., Kocsis, Sacha, Ho, Joseph, Hall, Michael J. W., Ferreyrol, Franck, Bennet, Adam, Ralph, Timothy C. and Pryde, Geoff J. (2014). Entanglement and simplified quantum information operations. Frontiers in Optics 2014, Tucson, AZ, United States, 19–23 October 2014. Washington DC United States: Optical Society of America (OSA). doi: 10.1364/FIO.2014.FW4C.1

Entanglement and simplified quantum information operations

2014

Conference Publication

Experimental verification of quantum discord in continuousvariable states and operational significance of discord consumption

Hosseini, Sara, Rahimi-Keshari, Saleh, Haw, Jing Yan, Assad, Syed M., Chrzanowski, Helen M., Janousek, Jiri, Symul, Thomas, Ralph, Timothy C., Lam, Ping Koy, Gu, Mile, Modi, Kavan and Vedral, Vlatko (2014). Experimental verification of quantum discord in continuousvariable states and operational significance of discord consumption. CLEO: QELS Fundamental Science (CLEO QELS 2014), San Jose, CA United States, 8-13 June 2014. Washington, DC United States: Optical Society of American (OSA). doi: 10.1364/cleo_qels.2014.fth3a.6

Experimental verification of quantum discord in continuousvariable states and operational significance of discord consumption

2014

Conference Publication

Boson sampling with continuous variable measurements

Ralph, Timothy (2014). Boson sampling with continuous variable measurements. Frontiers in Optics, FiO 2016, Rochester, NY, 17-21 October 2016. Washington, D.C.: OSA - The Optical Society. doi: 10.1364/FIO.2016.FF1C.2

Boson sampling with continuous variable measurements

2014

Conference Publication

Discord as a quantum resource for bi-partite communication

Chrzanowski, Helen M., Gu, Mile, Assad, Syed M., Symul, Thomas, Modi, Kevan, Ralph, Timothy C., Vedral, Vlatko and Lam, Ping Koy (2014). Discord as a quantum resource for bi-partite communication. 11th International Conference on Quantum Communication, Measurement and Computation, QCMC 2012, Vienna, Austria, 30 July- 3 August 2012. College Park, MD United States: American Institute of Physics. doi: 10.1063/1.4903110

Discord as a quantum resource for bi-partite communication

2014

Journal Article

Entanglement decoherence in a gravitational well according to the event formalism

Ralph, T. C. and Pienaar, J. (2014). Entanglement decoherence in a gravitational well according to the event formalism. New Journal of Physics, 16 (8) 085008, 1-12. doi: 10.1088/1367-2630/16/8/085008

Entanglement decoherence in a gravitational well according to the event formalism

2014

Conference Publication

Quantum non-Gaussian and Gaussian states at multiple side-band frequencies

Kuntz, Katanya B., Song, Hongbin, Webb, James G., Wheatley, Trevor A., Furusawa, Akira, Ralph, Timothy C. and Huntington, Elanor H. (2014). Quantum non-Gaussian and Gaussian states at multiple side-band frequencies. CLEO: QELS Fundamental Science (CLEO QELS 2014), San Jose, CA United States, 8-13 June 2014. Washington, DC United States: Optical Society of American (OSA). doi: 10.1364/cleo_qels.2014.fth3a.3

Quantum non-Gaussian and Gaussian states at multiple side-band frequencies

2013

Journal Article

Generation of distributed entangled coherent states over a lossy environment with inefficient detectors

Lund, A. P., Ralph, T. C. and Jeong, H. (2013). Generation of distributed entangled coherent states over a lossy environment with inefficient detectors. Physical Review A, 88 (5) 052335. doi: 10.1103/PhysRevA.88.052335

Generation of distributed entangled coherent states over a lossy environment with inefficient detectors

2013

Journal Article

Quantum communication: reliable teleportation

Ralph, Timothy C. (2013). Quantum communication: reliable teleportation. Nature, 500 (7462), 282-283. doi: 10.1038/500282a

Quantum communication: reliable teleportation

2013

Journal Article

High-fidelity teleportation of continuous-variable quantum states using delocalized single photons

Andersen, Ulrik L. and Ralph, Timothy C. (2013). High-fidelity teleportation of continuous-variable quantum states using delocalized single photons. Physical Review Letters, 111 (5) 050504, 050504.1-050504.5. doi: 10.1103/PhysRevLett.111.050504

High-fidelity teleportation of continuous-variable quantum states using delocalized single photons

2013

Journal Article

Quantum-state cloning in the presence of a closed timelike curve

Ahn, D., Myers, C. R., Ralph, T. C. and Mann, R. B. (2013). Quantum-state cloning in the presence of a closed timelike curve. Physical Review A, 88 (2) 022332, 022332.1-022332.5. doi: 10.1103/PhysRevA.88.022332

Quantum-state cloning in the presence of a closed timelike curve

2013

Journal Article

Quantum computation: boson sampling on a chip

Ralph, T. C. (2013). Quantum computation: boson sampling on a chip. Nature Photonics, 7 (7), 514-515. doi: 10.1038/nphoton.2013.175

Quantum computation: boson sampling on a chip

2013

Journal Article

Nondeterministic noiseless amplification via non-symplectic phase space transformations

Walk, Nathan, Lund, Austin P. and Ralph, Timothy C. (2013). Nondeterministic noiseless amplification via non-symplectic phase space transformations. New Journal of Physics, 15 (7) 073014, 073014.1-073014.23. doi: 10.1088/1367-2630/15/7/073014

Nondeterministic noiseless amplification via non-symplectic phase space transformations

2013

Journal Article

Direct characterization of linear-optical networks

Rahimi-Keshari, Saleh, Broome, Matthew A., Fickler, Robert, Fedrizzi, Alessandro, Ralph, Timothy C. and White, Andrew G. (2013). Direct characterization of linear-optical networks. Optics Express, 21 (11), 13450-13458. doi: 10.1364/OE.21.013450

Direct characterization of linear-optical networks

2013

Journal Article

Reconstruction of photon number conditioned states using phase randomized homodyne measurements

Chrzanowski, H. M., Assad, S. M., Bernu, J., Hage, B., Lund, A. P., Ralph, T. C., Lam, P. K. and Symul, T. (2013). Reconstruction of photon number conditioned states using phase randomized homodyne measurements. Journal of Physics B: Atomic, Molecular, and Optical Physics, 46 (10) 104009, 104009.1-104009.10. doi: 10.1088/0953-4075/46/10/104009

Reconstruction of photon number conditioned states using phase randomized homodyne measurements

2013

Journal Article

Quantum cryptography: continuous improvement

Lam, P. K. and Ralph, T. C. (2013). Quantum cryptography: continuous improvement. Nature Photonics, 7 (5), 350-352. doi: 10.1038/nphoton.2013.104

Quantum cryptography: continuous improvement

2013

Journal Article

Calculating unknown eigenvalues with a quantum algorithm

Zhou, Xiao-Qi, Kalasuwan, Pruet, Ralph, Timothy C. and O'Brien, Jeremy L. (2013). Calculating unknown eigenvalues with a quantum algorithm. Nature Photonics, 7 (3), 223-228. doi: 10.1038/NPHOTON.2012.360

Calculating unknown eigenvalues with a quantum algorithm

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

Need help?

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communications@uq.edu.au