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)

81 - 100 of 429 works

2017

Journal Article

Quantum sampling problems, BosonSampling and quantum supremacy

Lund, A. P., Bremner, Michael J. and Ralph, T. C. (2017). Quantum sampling problems, BosonSampling and quantum supremacy. NPJ Quantum Information, 3 (1) 0018. doi: 10.1038/s41534-017-0018-2

Quantum sampling problems, BosonSampling and quantum supremacy

2017

Journal Article

Ultrafine entanglement witnessing

Shahandeh, Farid, Ringbauer, Martin, Loredo, Juan C. and Ralph, Timothy C. (2017). Ultrafine entanglement witnessing. Physical Review Letters, 118 (11) 110502, 110502-1-110502-5. doi: 10.1103/PhysRevLett.118.110502

Ultrafine entanglement witnessing

2017

Journal Article

Quantum repeaters using continuous-variable teleportation

Dias, Josephine and Ralph, T. C. (2017). Quantum repeaters using continuous-variable teleportation. Physical Review A, 95 (2) 022312. doi: 10.1103/PhysRevA.95.022312

Quantum repeaters using continuous-variable teleportation

2017

Journal Article

On the problem of non-zero word error rates for fixed-rate error correction codes in continuous variable quantum key distribution

Johnson, Sarah J., Lance, Andrew M., Ong, Lawrence, Shirvanimoghaddam, Mahyar, Ralph, T. C. and Symul, Thomas (2017). On the problem of non-zero word error rates for fixed-rate error correction codes in continuous variable quantum key distribution. New Journal of Physics, 19 (2) 023003, 023003. doi: 10.1088/1367-2630/aa54d7

On the problem of non-zero word error rates for fixed-rate error correction codes in continuous variable quantum key distribution

2017

Conference Publication

Quantum enhancement of signal-to-noise ratio for arbitrary coherent states using heralded linear amplifiers

Zhao, Jie, Dias, Josephine, Haw, Jing Yan, Bradshaw, Mark, Blandino, Remi, Symul, Thomas, Ralph, Timothy, Assad, Syed and Lam, Ping Koy (2017). Quantum enhancement of signal-to-noise ratio for arbitrary coherent states using heralded linear amplifiers. Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), Singapore, 31 July-4 August 2017. Piscataway, NJ United States: Institute of Electrical and Electronics Engineers. doi: 10.1109/CLEOPR.2017.8119107

Quantum enhancement of signal-to-noise ratio for arbitrary coherent states using heralded linear amplifiers

2017

Conference Publication

Surpassing the no-cloning limit with a heralded hybrid linear amplifier

Haw, Jing Yan, Zhao, Jie, Dias, Josephine, Assad, Syed M., Bradshaw, Mark, Blandino, Remi, Symul, Thomas, Ralph, Timothy C. and Lam, Ping Koy (2017). Surpassing the no-cloning limit with a heralded hybrid linear amplifier. Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), Singapore, 31 July-4 August 2017. Piscataway, NJ United States: Institute of Electrical and Electronics Engineers. doi: 10.1109/CLEOPR.2017.8119040

Surpassing the no-cloning limit with a heralded hybrid linear amplifier

2016

Journal Article

Surpassing the no-cloning limit with a heralded hybrid linear amplifier for coherent states

Haw, Jing Yan, Zhao, Jie, Dias, Josephine, Assad, Syed M., Bradshaw, Mark, Blandino, Remi, Symul, Thomas, Ralph, Timothy C. and Lam, Ping Koy (2016). Surpassing the no-cloning limit with a heralded hybrid linear amplifier for coherent states. Nature Communications, 7 (1) 13222, 13222. doi: 10.1038/ncomms13222

Surpassing the no-cloning limit with a heralded hybrid linear amplifier for coherent states

2016

Journal Article

Black hole field theory with a firewall in two spacetime dimensions

Ho, C. T. Marco, Su, Daiqin, Mann, Robert B. and Ralph, Timothy C. (2016). Black hole field theory with a firewall in two spacetime dimensions. Physical Review D, 94 (8) 081502. doi: 10.1103/PhysRevD.94.081502

Black hole field theory with a firewall in two spacetime dimensions

2016

Journal Article

Arbitrary multi-qubit generation

Shahandeh, F., Lund, A. P., Ralph, T. C. and Vanner, M. R. (2016). Arbitrary multi-qubit generation. New Journal of Physics, 18 (10) 103020, 103020. doi: 10.1088/1367-2630/18/10/103020

Arbitrary multi-qubit generation

2016

Journal Article

A certification scheme for the boson sampler

Liu, Kai, Lund, Austin Peter, Gu, Yong-Jian and Ralph, Timothy Cameron (2016). A certification scheme for the boson sampler. Journal of the Optical Society of America B, 33 (9), 1835-1841. doi: 10.1364/JOSAB.33.001835

A certification scheme for the boson sampler

2016

Journal Article

Sufficient conditions for efficient classical simulation of quantum optics

Rahimi-Keshari, Saleh, Ralph, Timothy C. and Caves, Carlton M. (2016). Sufficient conditions for efficient classical simulation of quantum optics. Physical Review X, 6 (2) 021039, 165-171. doi: 10.1103/PhysRevX.6.021039

Sufficient conditions for efficient classical simulation of quantum optics

2016

Journal Article

Experimental demonstration of Gaussian protocols for one-sided device-independent quantum key distribution

Walk, Nathan, Hosseini, Sara, Geng, Jiao, Thearle, Oliver, Haw, Jing Yan, Armstrong, Seiji, Assad, Syed M., Janousek, Jiri, Ralph, Timothy C., Symul, Thomas, Wiseman, Howard M. and Lam, Ping Koy (2016). Experimental demonstration of Gaussian protocols for one-sided device-independent quantum key distribution. Optica, 3 (6) 259870, 634-642. doi: 10.1364/OPTICA.3.000634

Experimental demonstration of Gaussian protocols for one-sided device-independent quantum key distribution

2016

Journal Article

Estimating spacetime parameters with a quantum probe in a lossy environment

Kish, S. P. and Ralph, T. C. (2016). Estimating spacetime parameters with a quantum probe in a lossy environment. Physical Review D - Particles, Fields, Gravitation and Cosmology, 93 (10), 105013-1-105013-14. doi: 10.1103/PhysRevD.93.105013

Estimating spacetime parameters with a quantum probe in a lossy environment

2016

Journal Article

Models of reduced-noise, probabilistic linear amplifiers

Combes, Joshua, Walk, Nathan, Lund, A. P., Ralph, T. C. and Caves, Carlton M. (2016). Models of reduced-noise, probabilistic linear amplifiers. Physical Review A - Atomic, Molecular, and Optical Physics, 93 (5) 052310, 052310.1-052310.12. doi: 10.1103/PhysRevA.93.052310

Models of reduced-noise, probabilistic linear amplifiers

2016

Journal Article

A quantum Fredkin gate

Patel, Raj B., Ho, Joseph, Ferreyrol, Franck, Ralph, Timothy C. and Pryde, Geoff J. (2016). A quantum Fredkin gate. Science Advances, 2 (3) e1501531, e1501531. doi: 10.1126/sciadv.1501531

A quantum Fredkin gate

2016

Journal Article

Spacetime diamonds

Su, Daiqin and Ralph, T. C. (2016). Spacetime diamonds. Physical Review D, 93 (4) 044023. doi: 10.1103/PhysRevD.93.044023

Spacetime diamonds

2016

Journal Article

Channel purification via continuous-variable quantum teleportation with Gaussian postselection

Blandino, Remi, Walk, Nathan, Lund, Austin P. and Ralph, Timothy C. (2016). Channel purification via continuous-variable quantum teleportation with Gaussian postselection. Physical Review A - Atomic, Molecular, and Optical Physics, 93 (1) 012326. doi: 10.1103/PhysRevA.93.012326

Channel purification via continuous-variable quantum teleportation with Gaussian postselection

2016

Conference Publication

New directions in optical quantum computing

Ralph, T. C. (2016). New directions in optical quantum computing. 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, Busan, South Korea, 24 - 28 August 2015. Piscataway, NJ, United States: Institute of Electrical and Electronics Engineers . doi: 10.1109/CLEOPR.2015.7375881

New directions in optical quantum computing

2016

Conference Publication

Near-deterministic Bell measurement for multiphoton quantum information processing

Lee, Seung-Woo, Park, Kimin, Ralph, Timothy C. and Jeong, Hyunseok (2016). Near-deterministic Bell measurement for multiphoton quantum information processing. 11th Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2015, Busan, Korea, 24-28 August 2015. Piscataway, NJ, United States: Institute of Electrical and Electronics Engineers . doi: 10.1109/CLEOPR.2015.7375885

Near-deterministic Bell measurement for multiphoton quantum information processing

2016

Conference Publication

Enhancing optical quantum channels

Lund, Austin and Ralph, Timothy C. (2016). Enhancing optical quantum channels. SPIE, San Diego, CA, United States, 28–29 August 2016. Bellingham, WA, United States: SPIE. doi: 10.1117/12.2237438

Enhancing optical quantum channels

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

    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

    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

    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

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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