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)

21 - 40 of 430 works

2022

Journal Article

Billiard-ball paradox for a quantum wave packet

Bishop, Lachlan G, Ralph, Timothy C and Costa, Fabio (2022). Billiard-ball paradox for a quantum wave packet. Classical and Quantum Gravity, 39 (17) 175007, 1-27. doi: 10.1088/1361-6382/ac8198

Billiard-ball paradox for a quantum wave packet

2022

Journal Article

Relativistic Bohmian trajectories of photons via weak measurements

Foo, Joshua, Asmodelle, Estelle, Lund, Austin P. and Ralph, Timothy C. (2022). Relativistic Bohmian trajectories of photons via weak measurements. Nature Communications, 13 (1) 4002, 4002. doi: 10.1038/s41467-022-31608-6

Relativistic Bohmian trajectories of photons via weak measurements

2022

Journal Article

Ideal quantum teleamplification up to a selected energy cutoff using linear optics

Guanzon, Joshua J., Winnel, Matthew S., Lund, Austin P. and Ralph, Timothy C. (2022). Ideal quantum teleamplification up to a selected energy cutoff using linear optics. Physical Review Letters, 128 (16) 160501, 160501. doi: 10.1103/physrevlett.128.160501

Ideal quantum teleamplification up to a selected energy cutoff using linear optics

2022

Journal Article

Quantum channel correction outperforming direct transmission

Slussarenko, Sergei, Weston, Morgan M., Shalm, Lynden K., Verma, Varun B., Nam, Sae-Woo, Kocsis, Sacha, Ralph, Timothy C. and Pryde, Geoff J. (2022). Quantum channel correction outperforming direct transmission. Nature Communications, 13 (1) 1832, 1832. doi: 10.1038/s41467-022-29376-4

Quantum channel correction outperforming direct transmission

2022

Journal Article

Realizing a rapidly switched Unruh-DeWitt detector through electro-optic sampling of the electromagnetic vacuum

Onoe, Sho, Guedes, Thiago L. M., Moskalenko, Andrey S., Leitenstorfer, Alfred, Burkard, Guido and Ralph, Timothy C. (2022). Realizing a rapidly switched Unruh-DeWitt detector through electro-optic sampling of the electromagnetic vacuum. Physical Review D, 105 (5) 056023. doi: 10.1103/PhysRevD.105.056023

Realizing a rapidly switched Unruh-DeWitt detector through electro-optic sampling of the electromagnetic vacuum

2022

Journal Article

Telefilters, telemirrors, and causality

Foo, Joshua, Onoe, Sho, Zych, Magdalena and Ralph, Timothy C. (2022). Telefilters, telemirrors, and causality. Physical Review A, 105 (3) 033711. doi: 10.1103/physreva.105.033711

Telefilters, telemirrors, and causality

2022

Journal Article

Simple and loss-tolerant free-space quantum key distribution using a squeezed laser

Hosseinidehaj, Nedasadat, Winnel, Matthew S. and Ralph, Timothy C. (2022). Simple and loss-tolerant free-space quantum key distribution using a squeezed laser. Physical Review A, 105 (3) 032602. doi: 10.1103/physreva.105.032602

Simple and loss-tolerant free-space quantum key distribution using a squeezed laser

2022

Journal Article

Quantum effects in rotating reference frames

Kish, S. P. and Ralph, T. C. (2022). Quantum effects in rotating reference frames. AVS Quantum Science, 4 (1) 011401, 011401-1. doi: 10.1116/5.0073436

Quantum effects in rotating reference frames

2022

Journal Article

Gravitational acceleration estimation with a nonlinear Mach–Zehnder interferometer

Esmaeilifar, Leili and Ralph, Timothy C. (2022). Gravitational acceleration estimation with a nonlinear Mach–Zehnder interferometer. Journal of the Optical Society of America B: Optical Physics, 39 (2), 421-426. doi: 10.1364/JOSAB.443339

Gravitational acceleration estimation with a nonlinear Mach–Zehnder interferometer

2021

Journal Article

Multimode metrology via scattershot sampling

Guanzon, Joshua J., Lund, Austin P. and Ralph, Timothy C. (2021). Multimode metrology via scattershot sampling. Physical Review A, 104 (3) 032607. doi: 10.1103/physreva.104.032607

Multimode metrology via scattershot sampling

2021

Journal Article

Minimization of information leakage in continuous-variable quantum key distribution

Winnel, Matthew S., Hosseinidehaj, Nedasadat and Ralph, Timothy C. (2021). Minimization of information leakage in continuous-variable quantum key distribution. Physical Review A, 104 (1) 012411. doi: 10.1103/physreva.104.012411

Minimization of information leakage in continuous-variable quantum key distribution

2021

Journal Article

Time-traveling billiard-ball clocks: A quantum model

Bishop, Lachlan G., Costa, Fabio and Ralph, Timothy C. (2021). Time-traveling billiard-ball clocks: A quantum model. Physical Review A, 103 (4) 042223, 1-13. doi: 10.1103/physreva.103.042223

Time-traveling billiard-ball clocks: A quantum model

2021

Journal Article

Composable finite-size effects in free-space continuous-variable quantum-key-distribution systems

Hosseinidehaj, Nedasadat, Walk, Nathan and Ralph, Timothy C. (2021). Composable finite-size effects in free-space continuous-variable quantum-key-distribution systems. Physical Review A, 103 (1) 012605. doi: 10.1103/PhysRevA.103.012605

Composable finite-size effects in free-space continuous-variable quantum-key-distribution systems

2020

Journal Article

Generalized quantum scissors for noiseless linear amplification

Winnel, Matthew S., Hosseinidehaj, Nedasadat and Ralph, Timothy C. (2020). Generalized quantum scissors for noiseless linear amplification. Physical Review A, 102 (6) 063715. doi: 10.1103/physreva.102.063715

Generalized quantum scissors for noiseless linear amplification

2020

Journal Article

Spinning up a time machine

Ralph, T. C. and Chang, Christopher (2020). Spinning up a time machine. Physical Review D, 102 (12) 124013, 1-6. doi: 10.1103/physrevd.102.124013

Spinning up a time machine

2020

Journal Article

Quantum repeater for continuous-variable entanglement distribution

Dias, Josephine, Winnel, Matthew S., Hosseinidehaj, Nedasadat and Ralph, Timothy C. (2020). Quantum repeater for continuous-variable entanglement distribution. Physical Review A, 102 (5) 052425, 1-10. doi: 10.1103/PhysRevA.102.052425

Quantum repeater for continuous-variable entanglement distribution

2020

Journal Article

Maximum entanglement of formation for a two-mode Gaussian state over passive operations

Tserkis, Spyros, Thompson, Jayne, Lund, Austin P., Ralph, Timothy C., Lam, Ping Koy, Gu, Mile and Assad, Syed M. (2020). Maximum entanglement of formation for a two-mode Gaussian state over passive operations. Physical Review A, 102 (5) 052418. doi: 10.1103/PhysRevA.102.052418

Maximum entanglement of formation for a two-mode Gaussian state over passive operations

2020

Journal Article

Multipartite Gaussian entanglement of formation

Onoe, Sho, Tserkis, Spyros, Lund, Austin P. and Ralph, Timothy C. (2020). Multipartite Gaussian entanglement of formation. Physical Review A, 102 (4) 042408. doi: 10.1103/PhysRevA.102.042408

Multipartite Gaussian entanglement of formation

2020

Journal Article

Controllable quantum interference from two-photon scattershot sources

Guanzon, Joshua J., Lund, Austin P. and Ralph, Timothy C. (2020). Controllable quantum interference from two-photon scattershot sources. Physical Review A, 102 (3) 032606. doi: 10.1103/physreva.102.032606

Controllable quantum interference from two-photon scattershot sources

2020

Journal Article

Generating multi-partite entanglement from the quantum vacuum with a finite-lifetime mirror

Foo, Joshua, Onoe, Sho, Zych, Magdalena Anna and Ralph, Timothy C. (2020). Generating multi-partite entanglement from the quantum vacuum with a finite-lifetime mirror. New Journal of Physics, 22 (8) 083075, 083075. doi: 10.1088/1367-2630/aba1b2

Generating multi-partite entanglement from the quantum vacuum with a finite-lifetime mirror

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 information processing with linear optics

    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

    Beyond quantum field theory on a curved background

    Principal Advisor

  • Master Philosophy

    Resolving paradoxes of closed timelike curves

    Principal Advisor

  • 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

  • Doctor Philosophy

    Demonstration of relativistic Bohmian trajectories of photons

    Associate Advisor

    Other advisors: Dr Daniel Peace, Associate Professor Jacqui Romero

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