A5007213391- Diamond and Carbon-based Materials Research
- Advanced Fiber Laser Technologies
- Nonlinear Optical Materials Studies
- Force Microscopy Techniques and Applications
- High-pressure geophysics and materials
- Metal and Thin Film Mechanics
- Quantum optics and atomic interactions
- Ion-surface interactions and analysis
- Atomic and Subatomic Physics Research
- Carbon Nanotubes in Composites
- Laser-Matter Interactions and Applications
- Laser-Ablation Synthesis of Nanoparticles
- Photonic Crystals and Applications
- Electronic and Structural Properties of Oxides
- Photonic and Optical Devices
- Semiconductor materials and devices
- Advanced Fiber Optic Sensors
- Quantum Information and Cryptography
- Advanced Surface Polishing Techniques
- Photonic Crystal and Fiber Optics
- Graphene research and applications
- Mechanical and Optical Resonators
- Quantum and electron transport phenomena
- Solid State Laser Technologies
- Dust and Plasma Wave Phenomena
Macquarie University
2007-2013
Deloitte (United Kingdom)
2013
ARC Centre of Excellence for Engineered Quantum Systems
2011-2012
Centre for Quantum Computation and Communication Technology
2007-2011
Quantum (Australia)
2006-2010
Materials Science & Engineering
2009
Commonwealth Scientific and Industrial Research Organisation
2009
Centre for Ultrahigh Bandwidth Devices for Optical Systems
2009
The University of Melbourne
2005-2007
Heriot-Watt University Malaysia
2004
Lifetime limited optical excitation lines of single nitrogen vacancy (NV) defect centers in diamond have been observed at liquid helium temperature. They display unprecedented spectral stability over many seconds and cycles. Spectral tuning the spin selective resonances was performed via application an external electric field (i.e. Stark shift). A rich variety shifts were including linear as well quadratic components. The ability to tune NV has potential applications quantum information processing.
Coherent population trapping is demonstrated in single nitrogen-vacancy centers diamond under optical excitation. For sufficient excitation power, the fluorescence intensity drops almost to background level when laser modulation frequency matches 2.88 GHz splitting of ground states. The results are well described theoretically by a four-level model, allowing relative transition strengths be determined for individual centers. show that all-optical control spins possible diamond.
Nitrogen-vacancy (NV-) color centers in diamond were created by implantation of 7 keV 15N (I = 1/2) ions into type IIa diamond. Optically detected magnetic resonance was employed to measure the hyperfine coupling NV- centers. The spectrum from 15NV- arising implanted can be distinguished 14NV- native 14N 1) sites. Analysis indicates 1 40 atoms give rise an optically observable center. This report ultimately demonstrates a mechanism which yield center formation nitrogen measured.
The machining of 3D microstructures in single-crystal artificial diamond is demonstrated with a focused ion beam (FIB)-assisted lift-off technique. A sacrificial buried layer created MeV implantation, followed by patterning selected regions the FIB technique; then selectively etched, leaving free-standing bulk (see Figure). Using this fabrication technique, light waveguiding through microstructure for first time.
Nanodiamond crystals containing single color centers have been grown by chemical vapor deposition (CVD). The fluorescence from individual crystallites was directly correlated with crystallite size using a combined atomic force and scanning confocal microscope. Under the conditions employed, optimal for optically active nitrogen-vacancy (NV) center incorporation measured to be 60−70 nm. findings highlight strong dependence of NV on crystal size, particularly less than 50 nm in size.
Colored diamonds: Despite concerns that photostable luminescent nitrogen-vacancy (NV) centers do not exist in 5-nm diamonds, time-resolved luminescence experiments on weakly bound clusters of such diamonds show NV can be embedded (see picture). The efficiency formation scales as the fifth power crystal radius.
Recent progress in diamond growth via chemical vapor deposition (CVD) has enabled the manufacture of single crystal samples sufficient size and quality for realizing Raman laser devices. Here we report an external cavity CVD-diamond pumped by a Q-switched 532 nm laser. In investigated configuration, dominant output coupling was reflection loss at diamond's uncoated Brewster angle facets caused crystal's inherent birefringence. Output pulses wavelength 573 with combined energy 0.3 mJ were...
Abstract Control over the quantum states of individual luminescent nitrogen‐vacancy (NV) centres in nanodiamonds (NDs) is demonstrated by careful design crystal host: its size, surface functional groups, and interfacing substrate. By progressive etching ND host, NV are induced to switch from latent, through continuous, intermittent or “blinking” emission states. The blinking mechanism centre NDs elucidated a qualitative model proposed explain this phenomenon terms electron(s) tunnelling...
The nitrogen vacancy (NV) center is the most widely studied single optical defect in diamond with great potential for applications quantum technologies. Development of practical single-photon devices requires an understanding emission under a range conditions and environments. In this work, we study properties NV nanodiamonds embedded air-like silica aerogel environment which provides new domain probing behavior centers nanoscale arrangement, rate governed primarily by crystal lattice...
Fabrication of single nickel-nitrogen (NE8) defect centers in diamond by chemical vapor deposition is demonstrated. Under continuous-wave 745nm laser excitation defects were induced to emit photon pulses at 797nm with a linewidth 1.5nm room temperature. Photon antibunching was demonstrated using Hanbury–Brown and Twiss interferometer. Confocal images revealed approximately 106 optically active sites∕cm2 the synthesized films. The controlled fabrication an NE8 based source synthetic important...
This paper presents findings from a study of nanocrystalline diamond (NCD) growth in microwave plasma chemical vapour deposition (CVD) reactor. NCD films were grown using Ar/H2/CH4 and He/H2/CH4 gas compositions. The resulting characterised Raman spectroscopy, scanning electron microscopy atomic force microscopy. Analysis revealed an estimated grain size the order 50 nm, rates range 0.01 to 0.3 um/h sp3 sp2 bonded carbon content consistent with that expected for NCD. C2 Swan band was probed...
Fluorescent defects in noncytotoxic diamond nanoparticles are candidates for qubits quantum computing, optical labels biomedical imaging, and sensors magnetometry. For each application these need to be optically thermodynamically stable included individual particles at suitable concentrations (singly or large numbers). In this Letter, we combine simulations, theory, experiment provide the first comprehensive generic prediction of size, temperature, nitrogen-concentration-dependent stability...
The necessary elements for practical devices exploiting quantum coherence in diamond materials are summarized, and progress towards their realization documented. A brief review of future prospects diamond-based is also provided.
We report the realization of a solid-state triggered single-photon source with narrow emission in near infrared at room temperature. It is based on photoluminescence single nickel-nitrogen NE8 colour centre chemical vapour deposited diamond nanocrystal. Stable has been observed under both continuous-wave and pulsed excitations. The this represents step forward application diamond-based sources to Quantum Key Distribution (QKD) practical operating conditions.
Coherent population trapping at zero magnetic field was observed for nitrogen-vacancy centers in diamond under optical excitation.This measured as a reduction photoluminescence when the detuning between two excitation lasers matched 2.88 GHz crystal-field splitting of color center ground states.This behavior is highly sensitive to strain, which modifies excited states, and unexpected following recent experiments demonstrating readout single electron spins based on cycling transitions.These...
A technique has been developed for depositing diamond crystals on the endfaces of optical fibers and capturing fluorescence generated by optically active defects in into fiber. This letter details growth transmission through fiber from nitrogen-vacancy (N-V) color center diamond. Control concentration incorporated during chemical vapor deposition (CVD) process is also demonstrated. These are first critical steps developing a coupled single photon source based defect centers
Colour centres in diamond are promising candidates as a platform for quantum technologies and biomedical imaging based on spins and/or photons. Controlling the emission properties of colour is key requirement development efficient single-photon sources having high collection efficiency. A number groups have achieved an enhancement rate over narrow wavelength ranges by coupling single emitters nanodiamond crystals to resonant electromagnetic structures. In this paper, we characterize detail...
Bioprobes based on fluorescent ruby nanoparticles, which are suitable for ultrasensitive imaging, reported. A stable aqueous/buffer colloid, permitting facile conjugation to proteins, is produced by femtosecond laser ablation of and the nanoparticles (mean size 17 nm) photostable, with long lifetime (1–4 ms) 694 nm emission. With time‐gating complete (>20 dB) suppression cell autofluorescence exogenous fluorophores observed. Nanoparticles imaged in as‐grown cells those immunolabeled...