A5025971682- Quantum and electron transport phenomena
- Advancements in Semiconductor Devices and Circuit Design
- Semiconductor materials and devices
- Semiconductor Quantum Structures and Devices
- Molecular Junctions and Nanostructures
- Silicon Nanostructures and Photoluminescence
- Quantum Information and Cryptography
- Surface and Thin Film Phenomena
- Photonic and Optical Devices
- Semiconductor materials and interfaces
- Integrated Circuits and Semiconductor Failure Analysis
- Quantum optics and atomic interactions
- Quantum Computing Algorithms and Architecture
- Graphene research and applications
- Mechanical and Optical Resonators
- Nanowire Synthesis and Applications
- Photonic Crystals and Applications
- Electron and X-Ray Spectroscopy Techniques
- Magnetic properties of thin films
- Material Dynamics and Properties
- Diamond and Carbon-based Materials Research
- Theoretical and Computational Physics
- Glass properties and applications
- Electronic and Structural Properties of Oxides
- Quantum-Dot Cellular Automata
Centre for Quantum Computation and Communication Technology
2016-2025
UNSW Sydney
2016-2025
Australian Research Council
2014-2018
Delft University of Technology
2006-2017
Quantum (Australia)
2014
University of Liège
2007-2010
Hebrew University of Jerusalem
2007-2010
Institut polytechnique de Grenoble
2010
CEA Grenoble
2010
Institut Nanosciences et Cryogénie
2010
This review describes recent groundbreaking results in Si, $\mathrm{Si}/\mathrm{SiGe}$, and dopant-based quantum dots, it highlights the remarkable advances Si-based physics that have occurred past few years. progress has been possible thanks to materials development of Si devices, physical understanding effects silicon. Recent critical steps include isolation single electrons, observation spin blockade, single-shot readout individual electron spins both dopants gated dots Si. Each these...
The exceptionally long quantum coherence times of phosphorus donor nuclear spin qubits in silicon, coupled with the proven scalability silicon-based nano-electronics, make them attractive candidates for large-scale computing. However, high threshold topological error correction can only be captured a two-dimensional array operating synchronously and parallel-posing formidable fabrication control challenges. We present an architecture that addresses these problems through novel shared-control...
We report on spectroscopy of a single dopant atom in silicon by resonant tunneling between source and drain gated nanowire etched from insulator. The electronic states this isolated the channel appear as resonances low temperature conductance at energies below conduction band edge. observe two possible charge successively occupied spin-up spin-down electrons under magnetic field. first resonance is consistent with binding energy neutral D0 state an arsenic donor. second shows reduced...
A generally applicable model is presented to describe the potential barrier shape in ultra small Schottky diodes. It shown that for diodes smaller than a characteristic length $l_c$ (associated with semiconductor doping level) conventional description no longer holds. For such thickness decreases decreasing diode size. As consequence, resistance of strongly reduced, due enhanced tunneling. Without necessity assuming reduced (non-bulk) height, this effect provides an explanation several...
The ability to convert quantum states from microwave photons optical is important for hybrid system approaches information processing. We report the up-conversion of a signal into telecommunications wavelength band using erbium dopants in yttrium orthosilicate crystal via stimulated Raman scattering. microwaves were applied sample three-dimensional copper loop-gap resonator and coupling fields single passed. conversion efficiency was low, agreement with theoretical analysis, but can be...
Abstract In quantum simulation, many-body phenomena are probed in controllable systems. Recently, simulation of Bose–Hubbard Hamiltonians using cold atoms revealed previously hidden local correlations. However, fermionic Hubbard such as unconventional superconductivity and spin liquids more difficult to simulate atoms. To date the required single-site measurements cooling remain problematic, while only ensemble have been achieved. Here we a two-site Hamiltonian at low effective temperatures...
A new level of anisotropic plasmonic laser printing for aluminum multifunctional metasurfaces.
For solid-state spin qubits, single-gate rf readout can minimize the number of gates required for scale-up since sensor integrate into existing used to manipulate qubits. However, state-of-the-art topological error correction codes benefit from ability resolve qubit state within a single shot, that is, without repeated measurements. Here, we demonstrate single-gate, single-shot singlet-triplet in silicon, with an average fidelity 82.9% at 3.3 kHz measurement bandwidth. We use this technique...
Spin states in semiconductors provide exceptionally stable and noise-resistant environments for qubits, positioning them as optimal candidates reliable quantum computing technologies. The proposal to use nuclear electronic spins of donor atoms silicon, introduced by Kane 1998, sparked a new research field focused on the precise individual impurity devices, utilising scanning tunnelling microscopy ion implantation. This roadmap article reviews advancements 25 years since Kane's proposal,...
We report the observation of ambipolar transport in field-effect transistors fabricated on single crystals Copper- and Iron-Phthalocyanine, using gold as a high work-function metal for fabrication source drain electrodes. In these devices, room-temperature mobility holes reaches 0.3 cm$^2$/Vs both materials. The highest electrons is observed Iron-Phthalocyanines approximately one order magnitude lower. Our measurements indicate that values are limited by extrinsic contact effects due to...
We present a variable temperature scanning tunneling microscopy and spectroscopy study of the Si(553)-Au atomic chain reconstruction. This quasi-one-dimensional system undergoes at least two charge density wave (CDW) transitions, which can be attributed to electronic instabilities in fractionally filled 1D bands high-symmetry phase. Upon cooling, first single-band Peierls distortion, resulting period doubling along chains. state is ultimately overcome by competing x3 CDW, accompanied x2...
We report an insulator-metal-insulator transition in films of five metal phthalocyanines (MPc) doped with alkali atoms. Electrical conduction measurements demonstrate that increasing the concentration results formation a metallic state for all systems. Upon further doping, reenter insulating state. Structural and Raman spectroscopy studies reveal new crystalline phases upon doping are consistent phenomena originating from charge transfer between intercalated atoms MPc, similar fashion to...
Abstract Spin states of the electrons and nuclei phosphorus donors in silicon are strong candidates for quantum information processing applications given their excellent coherence times. Designing a scalable donor-based computer will require both knowledge relationship between device geometry electron tunnel couplings, spin readout strategy that uses minimal physical space device. Here we use radio frequency reflectometry to measure singlet–triplet few-donor Si:P double dot demonstrate...
Nanoscale single-electron pumps can be used to generate accurate currents, and potentially serve realize a new standard of electrical current based on elementary charge. Here, we use silicon-based quantum dot with tunable tunnel barriers as an source quantized current. The charge transfer accuracy our pump dramatically enhanced by controlling the electrostatic confinement using purposely engineered gate electrodes. Improvements in operational robustness, well suppression non-adiabatic...
We have measured electrical transport across epitaxial, nanometer-sized metal–semiconductor interfaces by contacting CoSi2 islands grown on Si(111) with the tip of a scanning tunneling microscope. The conductance per unit area was found to increase decreasing diode area. Indeed, zero-bias be ∼104 times larger than expected from downscaling conventional diode. These observations are explained model, which predicts narrower barrier for small diodes and, therefore, greatly increased...
We report the response of amorphous dielectrics to large dc electric fields E. Upon rapid application field, ac susceptibility ${\ensuremath{\varepsilon}}^{\ensuremath{'}}$ increases abruptly and then decays logarithmically for $t\ensuremath{-}{t}_{0}\ensuremath{\approx}1$ ${10}^{5}$ sec. Slow field sweeps show a minimum in at present when sample was cooled from 300 K. If E is held fixed different value, second local develops that evident upon subsequent sweeps. temperature, frequency,...
We have performed a comparative study of the electronic properties six different electron-doped metal-phthalocyanine (MPc) compounds (ZnPc, CuPc, NiPc, CoPc, FePc, and MnPc), in which electron density is controlled by means potassium intercalation. Despite complexity these systems, we find that nature underlying molecular orbitals produces observable effects doping dependence electrical conductivity materials. For all MPc's added electrons are expected to occupy centered on ligands NiPc),...
Adiabatic shuttling of single impurity bound electrons to gate induced surface states in semiconductors has attracted much attention recent times, mostly the context solid-state quantum computer architecture. A transport spectroscopy experiment for first time was able probe Stark shifted spectrum a donor silicon buried close gate. Here we present full theoretical model involving large-scale mechanical simulations that used compute order interpret experimental data. Use atomistic...
Semiconductor nano-devices have been scaled to the level that transport can be dominated by a single dopant atom. In strong coupling case Kondo effect is observed when one electron bound Here, we report on spin as well orbital ground state. We experimentally than theoretically show how tune symmetry transition from SU(4) state, many body state forms singlet virtual exchange with leads, pure SU(2) function of magnetic field. The small size and s-like dopant, make it model system in which...
We report the electronic transport on n-type silicon single electron transistors (SETs) fabricated in complementary metal oxide semiconductor (CMOS) technology. The SETs (n-MOSSETs) are built within a pre-industrial fully depleted insulator (FDSOI) technology with thickness down to 10 nm 200 mm wafers. nominal channel size of 20 × nm2 is obtained by employing beam lithography for active and gate level patterning. Coulomb blockade stability diagram precisely resolved at 4.2 K it exhibits...