- Twisted magnetic topological insulator: When momentum-space topology meets real-space topology?
Prof. G. Chen's research
AoE & CRF & RIF Awards in HKU Physics
Area of Excellence
on Meta-optics, Meta-acoustics and Meta-devices
Project Coordinator: D.P. Tsai (PolyU)
Co-PIs: C.T. Chan (HKUST), P. Sheng (HKUST), S. Zhang (HKU), J.T.H. Li (HKUST), J. Zhu (PolyU), K.H. Fung (PolyU)
Co-Is: J. Pendry (Imperial College London), T. Tanaka (RIKEN)
Collaborators: J. Yao (UC Berkerly, USA), X. Zhang (HKU), M. Fink (ESCPI Paris Tech, France)
Area of Excellence
on 2D Materials Research: Fundamentals Towards Emerging Technologies
Project Coordinator: W. Yao (HKU)
Deputy PC & Co-PI: M.H. Xie (HKU)
Co-PIs: X.D. Cui (HKU), S. Zhang (HKU), D.K. Ki (HKU), H. Zhang (CityU), J.B. Xu (CUHK), S. Yang (CUHK), S.P.D. Lau (PolyU), N. Wang (HKUST), K.T. Law (HKUST)
Co-Is: J.H. Hao (PolyU), J.N. Wang (HKUST), Z.Y. Meng (HKU), T.T. Luu (HKU), W.D. Li (HKU), D.Y. Lei (CityU)
Collaborators: X.D. Xu (Univ. of Washington, Seattle), C.H. Jin (Zhejiang Univ.), M. Chhowalla (Cambridge), K.P. Loh (National Univ. of Singapore), Y.G. Ma (Zhejiang University), K.F. Mak (Cornell University)
Two-dimensional (2D) materials have a great potential to revolutionize microelectronics and information technology. The variety of 2D materials feature a wide range of material properties from metal, semiconductors, insulators to magnets and superconductors, as well as exotic physics associated with electrons’ quantum degrees of freedom (spin & valley) that could be exploited to encode and process information more efficiently. Their tiny thickness - just a few atoms at most - promises the ultimate miniaturization of devices, and unparalleled control of materials and device functions. Moreover, 2D materials feature an unprecedented flexibility in their assembly into heterostructures, through which new materials and device functionalities may emerge. This project aims to explore these exciting opportunities for revolutionizing electronics, optoelectronics and photonics, through a concerted effort addressing the fundamental issues from physics, materials synthesis to device engineering based on 2D materials.
Led by pioneers in the field of 2D materials, this AoE project is an inter-institutional (involving 5 universities) and interdisciplinary one covering physics, applied physics, chemistry, electrical engineering. The team will seek to sustain Hong Kong’s edge in the field through basic and applied research, with a long-term goal of developing new prototype devices that will have application and commercialization potentials for Hong Kong.
Project Home Page
Area of Excellence
on Probing the Fundamental Structure of Matter with High Energy Particle Collisions
Project Coordinator: M.C. Chu (CUHK)
Co-PIs: A. Cohen (HKUST), L.R. Flores Castillo (CUHK), Z.C. Gu (CUHK), W.H. Ki (HKUST), J.H.C. Lee (HKU), P.P.C. Lee (CUHK), T. Liu (HKUST), E. Lo (CUHK), K. Prokofiev (HKUST), K.P. Pun (CUHK), C.Y. Tsui (HKUST), Y.J. Tu (HKU), H. Tye (HKUST)
Co-Is: K.B. Luk (U.C. Berkeley and HKUST), C. Young (SLAC National Accelerator Laboratory and CUHK)
Collaborators: M. Kado (Laboratoire de l'Accélérateur Linéaire, Universite Paris-Sud), A. Lounis (Laboratoire de l'Accélérateur Linéaire, Universite Paris-Sud), S. McMahon (Science and Technology Facilities Council), A. Schaffer ((Laboratoire de l'Accélérateur Linéaire, Universite Paris-Sud), B. Zhou (University of Michigan)
Area of Excellence
on Theory, Modeling, and Simulation of Emerging Electronics
Project Coordinator: F.C. Zhang (HKU)
PIs: J. Wang (HKU), G.H. Chen (HKU), L.J. Jiang (HKU), H. Guo (McGill and HKU), W.C. Chew (UIUC and HKU), M.S. Chan (HKUST), P.C.H. Chan (PolyU)
Co-Is: X.D. Cui (HKU), W. Yao (HKU), E. Lam (HKU), D.S.H. Lo, (HKU), P.W.T. Pong (HKU), N. Wong (HKU), K.L. Wu (CUHK), J.N. Wang ( HKUST), Y.J. Yan (HKUST)
This is a multi-institutional interdisciplinary project held by The University of Hong Kong, The Hong Kong University of Science and Technology, and The Chinese University of Hong Kong, and is funded by the Areas of Excellence Scheme. The current project team comprises Professor Fu-Chun Zhang (Physics, HKU), Professor Philip Chan (Provost, PolyU), Professor Guanhua Chen (Chemistry, HKU), Professor Weng-Cho Chew (EE, HKU), Professor Hong Guo (Physics, McGill Univ.), Professor Jian Wang (Physics, HKU), and several co-investigators.
The project strives to develop a suite of multi-scale electronic design automation (EDA) tools ranging from atomistic simulation methods to circuit simulators and to electromagnetic solvers for electrical signals for emerging sub-22nm technology. With these tools, we will study the sub-22nm devices and their systems; and calculate their physical and dynamical properties, and explore the possible paradigm shifts of next generation electronics. Our objectives are specifically listed below:
- To simulate from first-principles the electrical properties and processes of sub-22nm devices with atomistic details
- To investigate lithography modeling, and to employ efficient electromagnetic solvers to simulate electrical signals, power delivery, crosstalk, interference, and noise in multi-scale complex integrated circuits
- To calculate and model the electrical, chemical and mechanical properties of new materials for sub-22nm technology
- To develop modeling tools for emerging spintronics
- To use electron beam lithography technology to fabricate the sub-22nm devices for measurement and calibration of the parameters in our EDA tools
- To develop a set of multi-scale EDA tools for emerging devices and integrated circuits
Project Home Page
CRF (Collaborative Research Fund) Awards in HKU Physics
C7037-22GF
HKU, HKUST
Many-body paradigm in quantum moiré material research
Project Coordinator: Z.Y. Meng (HKU)
Co-PIs: X. Dai (HKUST), B. Jäck (HKUST), D.K. Ki (HKU), J.W. Liu (HKUST), H.C. Po (HKUST), N. Wang (HKUST)
Collaborator: X.D. Cui (HKU)
Other than the weak-correlated materials on which our daily-life technologies based, such as silicon-based computers, solar cells, or lithium-ion batteries, novel materials based on strong electronic correlations are crucial for the development of the next-generation computing chips going beyond Moore’s law, lossless energy transmission through superconductors, and other modern technologies for the major challenges in our society. The emerging 2D quantum moiré materials, e.g., twisted bilayer graphene, and twisted transition metal dichalcogenides, are among the best candidates for future electronics. In these moiré materials, topological flat-bands reduces the kinetic energy so that interactions become dominant and can induce exotic phases of matter such as correlated insulators and superconductivity. In this project, we will combine theory, computation and experimental efforts together, to understand the interplay of topology and correlation physics in the quantum moiré materials from a truely quantum many-body perspective. And in this way, we will be able to develop the many-body paradigm in quantum moiré material and to bring in new fundamental physics discoveries and benefit the society with new generation of quantum materials.
C7012-21G
HKU, CityU, CUHK
Transport and dynamics of correlated quantum matter
Project Coordinator: S.Q. Shen (HKU)
Co-PIs: G. Chen (HKU), Z.C. Gu (CUHK), X. Li (CityU), C.J. Wang (HKU), S.Z. Zhang (HKU)
Dynamics and transport properties of interacting many-body physics constitute one of the most important problems in modern condensed matter physics. Conventional theories on transport such as Boltzmann equations rely on being able to describe the system as a congregation of weakly interacting particles. However, when interaction becomes very strong, as in the case of materials that are close to their quantum critical points or unitary Fermi gas, the quasi-particles are presumably not well defined and a reliable theoretical framework for transport is missing. The topology of the band structure in solids also strongly modifies the usual transport equations and leads to novel transport effects. In some correlated quantum matter, topologically nontrivial low-energy excitations become the main carriers for charge, spin and heat transport, giving rise to new phenomena. Another class of systems that cannot be captured by the conventional Boltzmann equation approach are those far from thermal equilibrium. In particular, novel nonequilibrium phases of matter such as many-body localization, discrete time crystals, and quantum many-body scar states have emerged in recent years as promising platforms for quantum control and quantum simulation purposes. In particular, the memory of the initial state in such systems may be retained for an extended period, making them useful for quantum information storage applications. The dynamic and transport properties of quantum systems determine potential applications of quantum materials in the future.
The objectives of the project are (1) to investigate the transport and dynamics in which band topology plays a crucial role; (2) to investigate the transport and dynamics in strongly interacting and correlated systems; and (3) to develop and apply new numerical techniques for calculating transport and dynamic properties in the correlated quantum systems. The team are expected to contribute new understandings of various transport and dynamic phenomena, to explore new effects and novel states of matter in condensed matter and cold atom systems, to form a strong team at the forefront in the proposed field with an impact on the international community, and to train Ph. D students who could be contributing as researchers in academia or industry and become productive members of the society. In the long term, it is expected that the research work would possibly help the area of identifying and understanding correlated quantum materials to realize application in industry such as topological electronic devices and quantum computation qubits.
C7035-20GF
HKU, CityU, HKUST, CUHK
Low-dimensional perovskite materials for efficient and stable light emitting diodes: Materials, devices and fundamental understanding
Project Coordinator: W.C.H. Choy (HKU)
Co-PIs: A.B. Djurišić (HKU), A. Rogach (CityU), H.B. Su (HKUST), K.S. Wong (HKUST), N. Zhao (CUHK)
Collaborators: O. Abdelsaboor (KAUST), Y.Z. Jin (ZJU)
Low-dimensional halide perovskite emitters including zero-dimensional quantum dots (QDs) and quasi two-dimensional (quasi-2D) perovskites with the advantages of quantum confinement effects have emerged as a novel class of revolutionary semiconductors with high color purity, wide color gamut, low cost and simple solution process for vivid natural-color yet cost-effective displays. However, perovskite materials commonly exhibit environmental instability due to humidity, light and/or elevated temperature significantly hindering their applications in light emitting diodes (LEDs) where reported lifetimes are commonly in the order of minutes. Furthermore, while blue, green, and red emitters are the primary components for display applications, the efficiency of blue emitters presently lags behind green/red emitters. Despite the daunting challenges, the properties of both classes of low-dimensional perovskite emitters are extremely sensitive to their compositions and synthesis conditions, which opens up potential pathways for enhancing both the photoluminescence quantum yield and environmental stability through designing the composition, structure and quality of the perovskites. Meanwhile, in order to achieve well performing and stable multilayer-structured perovskite LEDs (PeLEDs), present studies on materials of charge transport layers, interfacial engineering, and defect passivation are critical yet still inconclusive. Additionally, device physics, operation and degradation mechanisms are crucially important for both optimizing the device performances and understanding the deterioration of the performance over time to achieve the practical applications of PeLEDs. We propose to perform a comprehensively study of theoretical modeling and experimental analysis of PeLEDs covering materials, devices, and the underlying understanding of related physical processes. We aim to (1) fundamentally understand the relationship between low-dimensional perovskite synthesis and composition, nucleation, and the formation of non-radiative defects, (2) develop practical material synthesis approaches for highly luminescent and stable perovskite emitters, (3) establish device architectures yielding high performances in PeLEDs, (4) elucidate the relationship between the materials in multilayered structures and device performances, and (5) achieve state-of-art low-dimensional PeLEDs.
C6009-20GF
HKUST, CUHK, HKU
New phases of quantum matter in engineered atomic systems
Project Coordinator: G.B. Jo (HKUST)
Co-PIs: D. Wang (CUHK), Z.D. Wang (HKU), S.Z. Zhang (HKU)
C6017-20GF
HKUST, HKU
Dark Matter and the Universe
Project Coordinator: T. Liu (HKUST)
Co-PIs: T. Broadhurst (HKU), A. Cohen (HKUST), J.J.L. Lim (HKU), G.F. Smoot (HKUST), H.S.H. Tye (HKUST), Y. Wang (HKUST)
Collaborators: T. Chiueh (NTU), M.C. Chu (CUHK), J. Ren (IHEP), R.A. Windhorst (ASU), Y. Zhao (The University of Utah)
C7018-20G
HKU, PolyU
Controlling the moisture – towards stable and efficient flexible perovskite solar cells
Project Coordinator: A.B. Djurišić (HKU)
Co-PIs: S.P.T. Feng (HKU), G. Li (PolyU), W. Li (HKU), J.Y. Tang (HKU)
C7015-19G
HKU, IKERBASQUE, CEFCA, CUHK, UST
Measurement of the Neutrino Mass through the Effects of Relic Neutrinos on Cosmological Structure
Project Coordinator: J.J.L. Lim (HKU)
Co-PIs: T. Broadhurst (IKERBASQUE), J. Cenarro (CEFCA), M.C. Chu (CUHK), G. Smoot (UST)
Collaborators: L.R. Abramo (University of Sao Paulo), R.E. Angulo (DIPC), N.A. Bahcall (Princeton University), S. Bonoli (CEFCA), J.J.G. Cadenas (DIPC), Y.F. Cai (University of Science and Technology of China), K.C. Chan (Sun Yat-Sen University), J.M. Diego (IFCA), T. Dinh (Vietnam Academy of Sciences), R.A. Dupke (National Observatory of Brazil), R. Emami (Harvard-Smithsonian Center for Astrophysics), N. Kaiser (ENS), X. Kong (University of Science and Technology of China, W.T. Luo (Kavli IPMU), C.Y. Ng (HKU), M. Oguri (University of Tokyo), K. Umetsu (ASIAA), J.M. Vilchez (IAA), A. Zitrin (University of the Negev)
C6005-17G
HKUST, HKUST, CU, HKU
Quantum State Manipulation of Ultracold Atoms in Optical Lattices
Project Coordinator: S. W. Du (HKUST)
Co-Is: G.B. Jo (HKUST), D.J. Wang (CU), Z.D. Wang (HKU), S.Z. Zhang (HKU)
C7036-17W
HKU, PolyU, HKUST
Two-dimensional Transition-metal Dichalcogenides and Beyond - From Materials, Physics to Devices
Project Coordinator: M. H. Xie (HKU)
Co-Is: X.D. Cui (HKU), S.Q. Shen (HKU), W. Yao (HKU), J.N. Wang (HKUST), N. Wang (HKUST), J.H. Hao (PolyU)
Two-dimensional (2D) materials are at the center stage of condensed matter and material science research today. Besides transition-metal dichalcogenides (TMDs), which are the subject of our on-going collaborative research project, an increasing number of new 2D systems have been identified and suggested to be of high application potentials. Examples of the latter include single-layer black phosphorus, (Ga,In)Se, MnPX3(X=S, Se), CrSiTe3, and chromium halides (CrBr3, CrI3, RuCI3) that show magnetic orders in the 2D forms.
In the course of the on-going TMD research, the team members have made internationally recognized achievements and produced impactful results. Examples include experimental observations of spin and valley polarizations, record high electrical carrier mobility and quantum transport anomalies. On theory, we revealed magneto-optical properties of excitons and trions in monolayer WSe2, found topological mosaic in moiré superlattices of van der Waals heterobilayers. The team members have also embarked on researches of other 2D systems such as black phosphorus and (Ga,In)Se by experiments, CrSiTe3 and halides by theory. In this renewal application, we will build upon our strength and past achievements in TMD research and to extend our studies of some other 2D materials like single-layer phosphorus, (Ga,In)Se, and magnetic 2D films. Specifically, we will make concerted efforts by combining theory and experiments to fabricate high quality 2D samples, their hybrid and heterostructures for characterizations of novel electronic, magnetic and optical properties as well as new physics. We shall explore application potentials of these 2D materials and structures by fabricating conventional or new-concept devices and to test their performances and functionalities. The team will continue to make impactful research outputs and contribute to the advance of 2D research in both fundamental physics and applications.
C6026-16W
HKUST, HKUST, HKU, CU
Study of Topological Phases in Condensed Matter and Cold Atom Systems
Project Coordinator: K. T. Law (HKUST)
Co-Is: T.K. Ng (HKUST), S.Q. Shen (HKU), S.Z. Zhang (HKU), Q. Zhou (CU)
Ordinary band insulators cannot conduct electricity due to the presence of a band gap and it takes energy larger than the band gap to excite electrons in the material. Recently, new types of band insulators, called topological insulators, have been discovered. Topological insulators have a band gap in the bulk, similar to ordinary band insulators, such that exciting electrons in the bulk costs finite energy. However, topological insulators support conducting surface states and electric currents can be driven by an arbitrary small electric field.
HKU9/CRF/13G
HKU, PolyU, HKUST
Two-Dimensional Transistion-Metal Dichalocigenides - from Materials, Physics to Devices
Project Coordinator: M. H. Xie (HKU)
Co-Is: X.D. Cui (HKU), S.Q. Shen (HKU), W. Yao (HKU), J.N. Wang (HKUST), N. Wang (HKUST), J.H. Hao (PolyU)
Atomically thin two-dimensional (2D) transition-metal dichalcogenides (TMDCs) are attracting high interests due to their novel properties as well as the ultimate miniaturization in thickness that promises nano-electronics and nano-optoelectronics. They are semiconductors with multi-valley band structures where electrons are labeled both by the spin and valley pseudo-spins, offering ideal platforms to exploring new concept devices utilizing these internal degrees of freedom. Their visible frequency range direct band-gap is ideal for optoelectronic and solar energy applications.
Bulk TMDCs exist in the form of stacks of covalently bonded hexagonal quasi-2D lattices packed by weak van der Waals forces. Flakes of monolayer TMDCs can be prepared by micromechanical cleavage (e.g., using Scotch tape) and by ion- intercalation, for example. Using the “flake” samples, people have discovered interesting properties of these 2D materials. Prototype devices have been made to demonstrate the concepts and viability of using gapped 2D semiconductors for electronic devices. However because the flake samples are small and not very reproducible, explorations of such materials remain hindered by the availability of high quality wafer-scale samples. There is an increasing demand of better and wafer sized samples for characterization and device fabrications.
In this proposal, we bring together a team of active researchers of complementary background and expertise for a concerted effort aiming at (1) producing high quality wafer scale 2D TMDC samples; (2) exploring spin and valley related new physics and properties of 2D TMDCs and examining the effects of defects; (3) experimenting device fabrication and characterization. The collaboration of theoretical and experimental teams in this proposal will ensure a comprehensive and productive research program, leading to new findings that likely impact on the advance towards future nano- electronics and nano-optoelectronics.
HKUST3/CRF/13G
HKUST, CUHK, HKU
New Topological States in Cold Atom and Condensed Matter Physics Systems
Project Coordinator: T.K. Ng (HKUST)
Co-Is: K.T. Law (HKUST), S.Q. Shen (HKU), S.Z. Zhang (HKU), Q. Zhou (CUHK)
Topological state of matter is now considered to be the most exciting area of research in hard condensed matter physics because of their rich new physics, and because of their exciting promise for application in quantum information. Remarkably, as activities in topological matter flourishes, an independent dramatic development in cold atoms on the creation of synthetic gauge fields and spin-orbit coupling between atoms have brought these two exciting development together. The reason is that spin-orbit coupling is the basic ingredient for the construction of many topological matters, and the great flexibilities of cold atom experiments raises the hope to realise many topological states hard to achieve in condensed matter systems, as well as to realise many new topological states of fundamental interests unique to cold atoms. Our project combines the existing strength of researchers in the area of topological order at condensed matter systems (TK Ng, KT Law and SQ Shen) and researchers in Cold atoms (S.Z. Zhang and Q. Zhou) to build a strong theoretical research team to explore this new and exciting area of research.
CUHK4/CRF/13G
CUHK, HKUST, HKU
Searching for New Physics with the Large Hadron Collider
Project Coordinator: M.C. Chu (CUHK)
Co-Is: H.F. Chau (HKU), L. Flores Castillo (U. of Wisconsin), K.B. Luk (U.C. Berkeley and HKU), G.M.L. Shiu (HKUST), C. Young (Stanford Linear Accelerator Center and CUHK)
Built upon our successful experience in the Daya Bay Reactor Experiment and the supporting Aberdeen Tunnel Experiment, and the strong collaboration both between institutions in Hong Kong and between the Hong Kong team and leading institutes overseas and in China, we propose to form a Hong Kong experimental particle physics group to join the ATLAS Collaboration, one of the two major Large Hadron Collider (LHC) experiments at CERN. Deploying the largest detectors and highest energy particle accelerator in the world, the LHC experiments are well positioned for making breakthrough discoveries in fundamental physics. The LHC runs in 2011-3, even though still at roughly half of the designed energy, already produced a huge volume of data. The discovery of the Higgs particle is indeed a result of these runs. We plan to take up tasks on physics analysis of the data accumulated so far, to search for new physics beyond the Standard Model of Particle Physics, and on software development so that the analysis tools will be ready when the beam energy and luminosity both increase drastically with the new LHC run, in 2014.We plan to carry out analysis of the Higgs particle and search for heavy weak bosons W’ and Z’, supersymmetric partners, and dark matter particles. The upcoming upgrade of the ATLAS detector presents a window of opportunity for Hong Kong researchers to contribute to the hardware development of the ATLAS experiment. In particular, we will work on the hardware development, reconstruction and simulation of the muon system. This Hong Kong experimental particle physics group will be an important component of the newly formed Joint Center for Fundamental Physics, by physicists in CUHK, HKU, and HKUST. The group will also benefit from interacting with the particle theory and astrophysics groups under the Joint Center of Fundamental Physics. With the manpower and resources from CUHK, HKU and HKUST together, we believe we can make meaningful contributions to experimental particle physics, one of the most important endeavors in human being’s quest to understanding Nature.
HKUST4/CRF/13G
HKUST, CUHK, HKU
Research in Fundamental physics: from the Large Hadron Collider to the Universe
Project Coordinator: G.M.L. Shiu (HKUST)
Co-Is: H.S.H. Tye (HKUST), T. Liu (HKUST), H.B. Li (CUHK), K.S. Cheng (HKU)
Fundamental physics addresses some key questions of Nature: What are we made of? What are the fundamental forces and matter in Nature? What is the origin of our Universe? These questions are intimately connected. Although key questions in fundamental physics are few, in contrast to other areas of scientific research, they are some of the most challenging ones in science. Advance towards their comprehension and solution requires big teams of experimentalists to extract important data, whose implications lead theorists to explore new possibilities and to make the predictions for experimentalists to test.
With the discovery of the Higgs particle at CERN’s Large Hadron Collider (LHC) in the past year, we now have a rather complete picture of what we are made of: electrons, quarks and gluons, the latter two combine to form protons, neutrons and nuclei, while the masses of fundamental particles (electrons, quarks etc.) come from the Higgs field.
Meanwhile, game-changing discoveries in astrophysics and cosmology have shaped our understanding of Nature at large scales. Observational data reveal that all known matter constitutes less than 5% of the total energy-matter content of the universe, and the remaining 95% is made up of dark matter and dark energy. While the observational evidence for dark energy (Nobel Prize 2011) is compelling, its theoretical underpinning remains a great mystery. Likewise, the existence of dark matter opens the next frontier in particle physics: the search for new physics beyond the Standard Model that we now know. Importantly, physics of the large and the small are deeply intertwined. With precise data, we can probe with high accuracy the early universe where fundamental physics leaves its fingerprints. These measurements provide strong support for cosmic inflation in which the early universe was driven by an enormous dark energy, thus explaining the origin of the hot big bang.
Fundamental physics is a brand new initiative in Hong Kong. This proposal focuses on its theoretical aspects because we have now a critical mass of theoretical physicists in Hong Kong working on these areas while the experimental program is actively being developed. As fundamental physics enters a data-rich era, it is crucial for theorists and experimentalists to collaborate closely. Theoretical studies are key to understanding the vast amount of data and designing new search strategies. Our team comprises researchers with complimentary expertise in a wide range of interconnected areas in particle physics, astrophysics, and cosmology.
HKU8/CRF/11G
HKU, CUHK, HKUST
Quantum Control and Quantum Information Processing
Project Coordinator: Z.D. Wang (HKU)
Co-Is: W. Yao (HKU), H.F. Chau (HKU), R.B. Liu (CUHK), S. Du (HKUST)
Quantum control and quantum information processing using atomic optical systems and solid state systems are cutting edge sciences with applications in device science, communication, cryptography, and metrology. In this collaborative project, we bring together the existing research strength in these areas in Hong Kong to form a team to address important issues in these areas. In particular, we will concentrate on the experimental studies on quantum state control, quantum information processing, and quantum communications using systems including photons, atoms and artificial atoms in solids. These studies will be backed up by the theorists in our team. We expect that the collaborative research in this emerging interdisciplinary field will not only advance our understanding of the exotic quantum world, but also expand our imagination for tomorrow’s quantum technological innovation.
HKU10/CRF/08
HKU, CUHK, HKUST
Nano-Spintronics - Quantum Control of Electron Spins in Semiconductors
Project Coordinator: F.C. Zhang (HKU)
Co-Is (HKU-Physics): X.D. Cui, S.Q. Shen, M.H. Xie
Spin based electronics or spintronics as a new generation of electronics is an emerging field with a great promise to advance the semiconductor industry. Spintronics aims to use electron’s spin, a tiny magnet or compass, to replace the role of electric charge in electronics. Metallic spintronics has already had a lot of applications. One of the recent focuses is the generation, manipulation and detection of spin-current, a counterpart of charge current, which may open a new route in the future spintronics. In this group project we will consolidate the existing research strength in both experiment and theory to form a versatile team in Hong Kong to focus on the generation and detection of the spin current.
HKUST3/CRF/09
HKUST, HKBU, CUHK, HKU
Quantum Order in Novel Materials: Superconductivity and Topological Order
Project Coordinator: T.K. Ng (HKUST)
Co-Is (HKU-Physics): S.Q. Shen, Z.D. Wang, and F.C. Zhang
Iron-based (pnictides) superconductors and topological insulators are the most important discoveries in hard condensed matter physics in recent years. The two classes of materials exhibit the common feature of exotic quantum behaviors (quantum order). Elucidating the principles that govern the properties of these materials and exploring their technological implication are the goals of the physics community. The complexity in tackling the many intervening issues in this area calls for a collaborative approach. With the help of a previous Collaborative Research Grant, a research team to tackle this problem is ready. The proposal consolidates the team to study holistically the novel quantum order behind these materials and to explore the nature of general topological order, a key ingredient in quantum information science. Several team members have entered this new field with influential results already produced. The goal of the team is to continue the high-quality research and become internationally recognized.
CUHK3/CRF/10
CUHK, HKU, U.C. Berkeley (USA) and IHEP, CAS (China)
High Precision Measurement of Neutrino Oscillation at Daya Bay
Project Coordinator: M.C. Chu (CUHK)
Co-Is (HKU-Physics): K.S. Cheng, J.K.C. Leung and J.C.S. Pun
The recent discovery of neutrino oscillation – a neutrino travelling in space transforms from one type to another – has profound impacts on particle physics, astrophysics and cosmology. The Daya Bay Reactor Neutrino Oscillation Experiment aims to measure a key but yet unknown neutrino oscillation parameter, θ13, to an unprecedented precision of better than 3 degrees, which is critical to the design of future experimental tests of a possible explanation of why matter dominates anti -matter in the universe, a key condition for our existence.
The Hong Kong team has been an active member of the Daya Bay Collaboration, an international team with 38 institutions. We will contribute to the commissioning and monitoring of the experiment and analysis of data, with the help of a subsystem of the antineutrino detector built by our team. We will also design and construct a continuous radon monitoring system as well as a cover gas system to minimize radon contamination of the detectors.
More details please refer to here.
CityU6/CRF/08
CityU, HKUST, HKU
Studies of Fundamental Properties of Nanosurfaces and Selected Applications
Project Coordinator: M.A. Van Hove (CityU)
Co-Is (HKU-Physics): A. Djurisic and H.S. Wu
The performance of nanoscale devices is often dominated by their surface properties. For example, surfaces introduce undesired electronic states in electronic and optoelectronic devices constructed from semiconducting nanostructures. By contrast, surface activity should be enhanced in nanostructures used as antibacterial agents. To improve such performance, our aim is to provide quantitative atomic-scale information about nanoscale surfaces. Our project will achieve this by introducing a new methodology: we will intentionally design and fabricate novel and highly-controlled nanoplatforms that allow for the first time detailed determination of surface structure and modeling of their relevant surface properties.
RIF (Research Impact Fund) Awards in HKU Physics
R7035-21F
HKU, Stockholm University, Gdansk University of Technology, Universitè Libre de Bruxelles
Trustworthy quantum gadgets for secure online communication
Project Coordinator: G. Chiribella (HKU)
Co-PIs: H.K. Lo (HKU), R. Ramanathan (HKU), K.Y.K. Wong (HKU), M. Bourennane (Stockholm University), P. Horodecki (Gdansk University of Technology), S. Pironio (Universitè Libre de Bruxelles)
Collaborators: J. Barrett (Oxford Uni.), F. Brandao (Caltech and Amazon)
Quantum cryptography promises a revolution in our communication technologies, offering enhanced security based on the fundamental laws of Nature. This level of security is essential to protect today’s sensitive information, such as census data, medical data, and industrial plans, from being decrypted in the future when more powerful computational resources will become available. In the short term, quantum cryptography can already benefit a vast range of applications, such as e-commerce, secure internet browsing, online messaging, online games, and online polls. Quantum cryptosystems have already been successfully employed to secure bank transactions, ballots, and, more recently, phone calls and video-conferences. If broadly implemented, they could benefit society at large, bringing unprecedented security and opening up a new market of quantum-enhanced products.
Still, the full potential of quantum security has not been realized yet. Commercial implementations are secure, but only as long as the devices behave according to their specifications. A new generation of quantum protocols, called device-independent (DI) and semi-device-independent (SDI) guarantee security even in the extreme scenario where the devices have been manufactured by the hackers themselves. However, DI/SDI protocols are still far from being practical. The goal of this project is to circumvent the roadblocks to DI/SDI cryptography, and to bring it closer to businesses and ordinary users. To achieve this goal, we have formed a world-class team including leading experts from the International Centre for the Theory of Quantum Technologies (Gdansk), Stockholm University, and Université Libre de Bruxelles. Building on a unique combination of expertise covering both theory and experiment, we will develop secure protocols for key distribution and random number generation that can be implemented on devices of moderate size while tolerating noise, imperfect initial seeds, and defects in the measurement devices.
This project will build up a local expertise in Hong Kong in the field of quantum cryptography, and is likely to spawn new start-up ventures in the near future. In the longer term, the development of quantum-enhanced communication systems will contribute to create a secure digital future and to strengthen Hong Kong’s leadership in the technological and financial sectors.