A5055882839- Quantum and electron transport phenomena
- Topological Materials and Phenomena
- Magnetic properties of thin films
- Physics of Superconductivity and Magnetism
- Graphene research and applications
- Semiconductor Quantum Structures and Devices
- 2D Materials and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Electronic and Structural Properties of Oxides
- Quantum Information and Cryptography
- Semiconductor materials and devices
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum many-body systems
- Spectroscopy and Quantum Chemical Studies
- Advanced Thermoelectric Materials and Devices
- Pulsars and Gravitational Waves Research
- Quantum, superfluid, helium dynamics
- Machine Learning in Materials Science
- Magnetic Field Sensors Techniques
- Geomagnetism and Paleomagnetism Studies
- Advanced Physical and Chemical Molecular Interactions
- Chemical and Physical Properties of Materials
- Quantum optics and atomic interactions
Nanyang Technological University
2019-2024
UNSW Sydney
2017-2021
Australian Research Council
2018-2021
ARC Centre of Excellence in Future Low-Energy Electronics Technologies
2018-2021
The University of Queensland
2013
We theoretically investigate the properties of holes in a Si$_{x}$Ge$_{1-x}$/Ge/ Si$_{x}$Ge$_{1-x}$ quantum well perpendicular magnetic field that make them advantageous as qubits, including large ($>$100~meV) intrinsic splitting between light and heavy hole bands, very ($\sim$0.05$\, m_0$) in-plane effective mass, consistent with higher mobilities tunnel rates, larger dot sizes could ameliorate constraints on device fabrication. Compared to electrons dots, qubits do not suffer from presence...
Many semiconductor nanostructures are made from planar two-dimensional heterojunction systems. With a view to merging physics, spintronics, and quantum computing, strongly spin-orbit coupled systems such as holes have generated burgeoning research interest. While recent experiments in various low-dimensional hole shown great promise achieving electrical spin control, thorough understanding of interactions is lacking. Owing the intricate between their environment, calculations on...
The ordinary Hall effect is driven by the Lorentz force, while its anomalous counterpart occurs in ferromagnets. Here we show that Berry curvature monopole of non-magnetic 2D spin-3/2 holes leads to a novel linear an applied in-plane magnetic field B_x. There no force hence effect, all disorder contributions vanish leading order This intrinsic phenomenon, which term planar (APHE), provides non-quantized footprint topological transport directly accessible p-type semiconductors.
Abstract Quantum technologies are poised to move the foundational principles of quantum physics forefront applications. This roadmap identifies some key challenges and provides insights on material innovations underlying a range exciting technology frontiers. Over past decades, hardware platforms enabling different have reached varying levels maturity. has allowed for first proof-of-principle demonstrations supremacy, example computers surpassing their classical counterparts, communication...
Moiré superlattices of van der Waals structures offer a powerful platform for engineering band structure and quantum states. For instance, in magic-angle twisted bilayer graphene, ABC trilayer graphene have been shown to harbor correlated insulating superconducting states, while transition metal dichalcogenide (TMD) bilayers, excitons identified. Here we show that the effects superlattice on are general: In TMD exciton complexes can be trapped manner analogous ultracold bosonic or Fermionic...
Spin-orbit coupling is key to all-electrical control of quantum-dot spin qubits, and often much stronger for holes than electrons. The recent development high-quality hole nanostructures has generated considerable interest in hole-spin qubit architectures [C. Kloeffel D. Loss, Annu. Rev. Condens. Matter Phys. 4, 51 (2013)]. Yet quantum computing hinges on the ability discriminate between competing Zeeman terms understanding complex interplay spin-orbit interactions, which are probed via...
Semiconductor holes with strong spin-orbit coupling allow all-electrical spin control, broad applications ranging from spintronics to quantum computation. Using a two-dimensional hole system in gallium arsenide well, we demonstrate new mechanism of electrically controlling the Zeeman splitting, which is achieved through altering wave vector k. We find threefold enhancement in-plane g-factor g∥(k). introduce method for quantifying splitting magnetoresistance measurements, since conventional...
Classical charge transport, such as longitudinal and Hall currents in weak magnetic fields, is usually not affected by quantum phenomena. Yet relativistic mechanics at the heart of spin-orbit interaction, which has been forefront efforts to realize spin-based electronics, new phases matter, topological computing. In this work we demonstrate that spin dynamics induced interaction directly observable classical transport. We determine coefficient RH two-dimensional hole systems low fields show...
Abstract In one-dimensional (1D) systems, electronic interactions lead to a breakdown of Fermi liquid theory and the formation Tomonaga-Luttinger Liquid (TLL). The strength its many-body correlations can be quantified by single dimensionless parameter, Luttinger parameter K , characterising competition between electrons’ kinetic electrostatic energies. Recently, signatures TLL have been reported for topological edge states quantum spin Hall (QSH) insulators, strictly 1D structures with...
Abstract Strong spin-orbit interactions make hole quantum dots central to the quest for electrical spin qubit manipulation enabling fast, low-power, scalable computation. Yet it is important establish what extent coupling exposes qubits noise, facilitating decoherence. Here, taking Ge as an example, we show that group IV gate-defined generically exhibit optimal operation points, defined by top gate electric field, at which they are both fast and long-lived: dephasing rate vanishes first...
Abstract Three-dimensional Dirac semimetals with square-net non-symmorphic symmetry, such as ternary ZrXY (X = Si, Ge; Y S, Se, Te) compounds, have attracted significant attention owing to the presence of topological nodal lines, loops, or networks in their bulk. Orbital symmetry plays a profound role materials different branches dispersion can be distinguished by distinct orbital eigenvalues. The eigenvalues suggests that scattering between states may strongly suppressed. Indeed, ZrSiS,...
The Zeeman interaction is a quantum mechanical effect that underpins spin-based devices such as spin qubits. Typically, identification of the needs large out-of-plane magnetic field coupled with ultralow temperatures, which limits practicality devices. However, in two-dimensional (2D) semiconductor holes, strong spin-orbit causes to couple spin, field, and momentum, has terms different winding numbers. In this work, we demonstrate physical mechanism by can be detected classical transport....
3D Dirac semimetals with square-net non-symmorphic symmetry, such as ternary ZrXY (X=Si, Ge; Y=S, Se, Te) compounds, have attracted significant attention owing to the presence of topological nodal lines, loops, or networks in their bulk. Orbital symmetry plays a profound role materials different branches dispersion can be distinguished by distinct orbital eigenvalues. The eigenvalues suggests that scattering between states may strongly suppressed. Indeed, ZrSiS, there has been no clear...
In solid state conductors, linear response to a steady electric field is normally dominated by Bloch occupation number changes. Recently it has been realized that, for of important physical observables, the dominant electric-field induced coherence between states in different bands. Examples include anomalous and spin-Hall effects, spin torques magnetic minimum conductivity chiral anomaly Weyl Dirac semimetals. Here we first discuss framework general quantum kinetic theory an which can be...
The ability to convert spin accumulation charge currents is essential for applications in spintronics. In semiconductors, spin-to-charge conversion typically achieved using the inverse Hall effect or a large magnetic field. Here we demonstrate general method that exploits nonlinear interactions between and perform all-electrical, rapid, noninvasive detection of without need We operation this technique with ballistic GaAs holes as model system strong spin-orbit coupling, which quantum point...
Quantum technologies are poised to move the foundational principles of quantum physics forefront applications. This roadmap identifies some key challenges and provides insights on materials innovations underlying a range exciting technology frontiers. Over past decades, hardware platforms enabling different have reached varying levels maturity. has allowed for first proof-of-principle demonstrations supremacy, example computers surpassing their classical counterparts, communication with...
In one-dimensional (1D) systems, electronic interactions lead to a breakdown of Fermi liquid theory and the formation Tomonaga-Luttinger Liquid (TLL). The strength its many-body correlations can be quantified by single dimensionless parameter, Luttinger parameter $K$, characterising competition between electrons' kinetic electrostatic energies. Recently, signatures TLL have been reported for topological edge states quantum spin Hall (QSH) insulators, strictly 1D structures with linear...