A5061261786- Quantum Information and Cryptography
- Orbital Angular Momentum in Optics
- Quantum Mechanics and Applications
- Quantum Computing Algorithms and Architecture
- Quantum optics and atomic interactions
- Cold Atom Physics and Bose-Einstein Condensates
- Mechanical and Optical Resonators
- Random lasers and scattering media
- Digital Holography and Microscopy
- Optical Network Technologies
- Photonic and Optical Devices
- Neural Networks and Reservoir Computing
- Atomic and Subatomic Physics Research
- Optical Polarization and Ellipsometry
- Advanced Optical Imaging Technologies
- Nonlinear Optical Materials Studies
- Advanced Fiber Laser Technologies
- Experimental and Theoretical Physics Studies
- Computability, Logic, AI Algorithms
- Laser-Matter Interactions and Applications
- Image Processing Techniques and Applications
- Optical Coherence Tomography Applications
- Biofield Effects and Biophysics
- Liquid Crystal Research Advancements
- Scientific Research and Philosophical Inquiry
The University of Queensland
2016-2024
Australian Research Council
2020-2023
Quantum (Australia)
2021-2022
ARC Centre of Excellence for Engineered Quantum Systems
2018-2021
Centre for Quantum Computation and Communication Technology
2016-2020
Macquarie University
2018
Queensland University of Technology
2018
University of Glasgow
2009-2016
Centre for Quantum Technologies
2016
National University of Singapore
2016
Structured light refers to the generation and application of custom fields. As tools technology create detect structured have evolved, steadily applications begun emerge. This roadmap touches on key fields within from perspective experts in those areas, providing insight into current state challenges their respective face. Collectively outlines venerable nature research exciting prospects for future that are yet be realized.
Entanglement of the properties two separated particles constitutes a fundamental signature quantum mechanics and is key resource for information science. We demonstrate strong Einstein, Podolsky, Rosen correlations between angular position orbital momentum photons created by nonlinear optical process spontaneous parametric down-conversion. The discrete nature continuous but periodic give rise to special sort entanglement these variables. resulting are found be an order magnitude stronger...
Integrated photonics is at the heart of many classical technologies, from optical communications to biosensors, LIDAR, and data center fiber interconnects. There strong evidence that these integrated technologies will play a key role in quantum systems as they grow few-qubit prototypes tens thousands qubits. The underlying laser with required functionality performance, can only be realized through integration components onto photonic circuits (QPICs) accompanying electronics. In last decade,...
Quantum mechanics allows events to happen with no definite causal order: this can be verified by measuring a witness, in the same way that an entanglement witness verifies entanglement. Here, we realize photonic quantum switch, where two operations A^ and B^ act superposition of their possible orders. The are on transverse spatial mode photons; polarization coherently controls order. Our implementation ensures cannot distinguished or temporal position—further it qudit encoding target. We...
We demonstrate that the combination of digital spiral imaging with high-dimensional orbital angular momentum (OAM) entanglement can be used for efficiently probing and identifying pure phase objects, where light does not necessarily touch object, via experimental, non-local decomposition non-integer vortices in OAM-entangled photon pairs. The entangled photons are generated by parametric downconversion then measured spatial modulators single-mode fibers. fractional defined idler photons,...
We demonstrate the contrast enhancement of images within a ghost-imaging system by use nonlocal phase filters. parametric down-conversion as two-photon light source and two separated modulators, in signal idler arms which represent different filters objects, respectively. obtain edge enhanced direct consequence quantum correlations orbital angular momentum (OAM) down-converted photon pairs. For with differently orientated edges, we show violation Bell-type inequality for an OAM subspace,...
We observe entanglement between photons in controlled superposition states of orbital angular momentum (OAM).By drawing a direct analogy OAM and polarization light, we demonstrate the entangled nature high order generated by spontaneous downconversion through violation suitable Clauser Horne Shimony Holt (CHSH)-Bell inequality.We this number two-dimensional subspaces higher dimensional Hilbert space.
That the speed of light in free space is constant a cornerstone modern physics. However, beams have finite transverse size, which leads to modification their wavevectors resulting change phase and group velocities. We study velocity single photons by measuring arrival time that results from changing beam's spatial structure. Using time-correlated photon pairs we show reduction both Bessel beam focused Gaussian beam. In cases, delay several microns over propagation distance order 1 m. Our...
Any practical experiment utilising the innate D-dimensional entanglement of orbital angular momentum (OAM) state space photons is subject to modal capacity detection system. We show that given such a constraint, number measured, entangled OAM modes in photon pairs generated by spontaneous parametric down-conversion (SPDC) can be maximised tuning phase-matching conditions SPDC process. demonstrate factor 2 increase on half-width OAM-correlation spectrum, from 10 20, latter implying \approx 50...
Mutually unbiased bases (MUBs) play a key role in many protocols quantum science, such as distribution. However, defining MUBs for arbitrary high-dimensional systems is theoretically difficult, and measurements can be hard to implement. We show experimentally that efficient state reconstruction of multipartite system performed by considering only the individual parts. The spaces subsystems are always smaller than space composite system. Thus, benefit this method need defined small Hilbert...
High-dimensional entanglement has demonstrated its potential for increasing channel capacity and resistance to noise in quantum information processing. However, distributing it is a challenging task, imposing severe restrictions on application. Here we report the first distribution of three-dimensional orbital angular momentum (OAM) via 1-km-long few-mode optical fiber. Using an actively stabilizing phase precompensation technique, successfully transport one photon OAM entangled pair through...
Classically, no information can be transmitted through a depolarising, which is completely noisy, channel. We show that by combining depolarising channel with another in an indefinite causal order—that is, when there superposition of the order these two channels were applied—it becomes possible to transmit significant information. consider limiting cases. When both are fully ideal limit communication 0.049 bits; experimentally we achieve (3.4±0.2)×10−2 bits. one and other known unitary, 1...
The exponential growth in Hilbert space with increasing size of a quantum system means that accurately characterizing the becomes significantly harder dimension d. We show self-guided tomography is practical, efficient, and robust technique measuring higher-dimensional states. achieved fidelities are over 99.9% for qutrits (d=3) ququints (d=5), 99.1% quvigints (d=20)—the highest values ever realized qudit pure also excellent performance mixed states, achieving average 96.5% qutrits....
We use spatial light modulators (SLMs) to measure correlations between arbitrary superpositions of orbital angular momentum (OAM) states generated by spontaneous parametric down-conversion. Our technique allows us fully access a two-dimensional OAM subspace described Bloch sphere, within the higher-dimensional Hilbert space. quantify entanglement through violations Bell-type inequality for pairs modal that lie on equatorial, polar, and great circles sphere. work shows SLMs can be used with...
Optical vortices are lines of phase singularity which percolate through all optical fields. We report the entanglement linked vortex loops in light produced by spontaneous parametric down-conversion. As measured using a Bell inequality, this between topological features extends over macroscopic and finite volumes. The photons complex three-dimensional states suggests possibility similar other quantum systems describable scalar functions, such as superconductors, superfluids, Bose-Einstein...
Recent results in deeply subwavelength thickness films demonstrate coherent control and logical gate operations with both classical single-photon light sources. However, quantum processing devices typically involve more than one photon nontrivial input states. Here we experimentally investigate two-photon N00N state absorption a multilayer graphene film. Depending on the phase, it is possible to selectively choose between single- or of These that regime exhibits unique features, opening up...
Abstract High-dimensional time-frequency encodings have the potential to significantly advance quantum information science; however, practical applications require precise knowledge of encoded states, which becomes increasingly challenging for larger Hilbert spaces. Self-guided tomography (SGT) has emerged as a and scalable technique this purpose in spatial domain. Here, we apply SGT estimate states using multi-output pulse gate. We achieve fidelities more than 99% 3- 5-dimensional without...
In this paper we consider geometrical two-photon optics of Bessel-Gaussian modes generated in spontaneous parametric down-conversion a Gaussian pump beam. We provide general theoretical expression for the orbital angular momentum (OAM) spectrum and Schmidt number basis show how may be varied by control over radial degree freedom, continuous parameter modes. As test first implement back-projection technique to classically predict, experiment, quantum correlations produced three holographic...
We introduce and analyze approximate quantum secret sharing in a formal cryptographic setting, wherein dealer encodes distributes to players such that authorized structures (sets of subsets players) can approximately reconstruct the omnipotent adversarial agents controlling nonauthorized are denied secret. In particular, viewing map encoding shares for an structure as channel, we show reconstructability by these is possible if only information leakage, given terms certain...
We report an experimental test of Leggett's non-local hidden variable theory in orbital angular momentum (OAM) state space light. show that the correlations we observe are conflict with model, thus excluding a particular class theories for first time non-polarization space. It is known violation Leggett inequality becomes stronger as more detection settings used. The required measurements become feasible OAM subspace, and demonstrate this by testing using three four settings. excellent...
Most noise-characterization methods for quantum technologies assume Markovianity, meaning that the environment and system have no memory of their interactions with each other, because it is inefficient computationally demanding to take temporal correlations into account. Here, authors propose a more efficient machine learning method estimating non-Markovian noise implement in proof-of-principle optics experiment.
We report orbital angular momentum (OAM) and angle correlations between signal idler photons observed when the nonlinear crystal used in spontaneous parametric down-conversion is illuminated by a non-fundamental Gaussian pump beam. introduce π-phase step to transverse profile of pump, before it impinges on create phase-flipped mode, which close approximation an HG10 Hermite–Gaussian-like The OAM position are then measured holographically using two separate spatial light modulators arms. show...
Hardy's nonlocality proof is considered as "the best version of Bell's theorem". We report an experimental implementation this by measuring the orbital angular momentum (OAM) entangled twisted photon pairs. Two advantages arise from using photons. First, limited OAM spectrum generated parametric down-conversion provides a natural set non-maximally states with selective degrees entanglement. Second, measurement any non-trivial superposition can be conveniently done spatial light modulators....