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  • Dots
  • Colloidal quantum dots irradiated with a UV light. (wikipedia.org)
  • Different sized quantum dots emit different color light due to quantum confinement. (wikipedia.org)
  • Many types of quantum dot will emit light of specific frequencies if electricity or light is applied to them, and these frequencies can be precisely tuned by changing the dots' size, shape and material, giving rise to many applications. (wikipedia.org)
  • There are several ways to prepare quantum dots, the principal ones involving colloids. (wikipedia.org)
  • This corresponds to about 2 to 10 nanometers , and at 10 nm in diameter, nearly 3 million quantum dots could be lined up end to end and fit within the width of a human thumb. (wikipedia.org)
  • small
  • Additionally, their small size allows for QDs to be suspended in solution which leads to possible uses in inkjet printing and spin-coating . (wikipedia.org)
  • Mott
  • Spin-1/2 moments in the antiferromagnetic Mott insulator α-RuCl3 are coupled by strongly anisotropic bond-dependent exchange interactions on a honeycomb lattice. (case.edu)
  • Upon doping, Mott insulators often exhibit symmetry breaking where charge carriers and their spins organize into patterns known as stripes. (stanford.edu)
  • Here, we show that circularly polarized light can provide a knob to drive frustrated Mott insulators into a chiral spin liquid, realizing an elusive quantum spin liquid with topological order. (stanford.edu)
  • We find that the dynamics of a driven Kagome Mott insulator is well-captured by an effective Floquet spin model, with heating strongly suppressed, inducing a scalar spin chirality S i · (S j × S k ) term which dynamically breaks time-reversal while preserving SU(2) spin symmetry. (stanford.edu)
  • It shows how as one increases the number of deuterium atoms (replacing H) on the BEDT-TTF molecules (shown below) one gradually moves from the superconducting (S.C.) phase into the antiferromagnetic Mott insulator (A.F.I) phase. (blogspot.in)
  • Fermions
  • Furthermore, the properties of the spin-orbital liquid state on the honeycomb lattice are accurately accounted for by a projected variational wave-function based on the pi-flux state of fermions on the honeycomb lattice at 1/4-filling. (perimeterinstitute.ca)
  • Gil Refael is best known for his works on realizing Majorana fermions in solid state systems and on quantum dynamics and control. (simonsfoundation.org)
  • criticality
  • Another approach, often calles 'local' quantum criticality, supposes that the Kondo effect breaks down at the critical pressure as the f electrons are not coupled only to the conduction electrons, but also among themselves. (cea.fr)
  • Here we discuss consequences of quantum criticality at the onset of incommensurate 2 k F charge or spin density wave order in the ground state, in cases where the phase transition (e.g., as a function of electron density) is continuous. (mpg.de)
  • superconductors
  • Although solid-state systems are usually considered "dirty" with impurities and imperfections, it is still the case that macroscopic, quantized phenomena can be observed in the form of the Josephson effect in superconductors and the quantum Hall effect in 2DEG. (case.edu)
  • Called quantized vortices, they exist only in superfluids or superfluid-like systems such as liquid helium, type-II superconductors, liquid crystals, Bose-Einstein condensates, the inner cores of neutron stars, and perhaps cosmic strings in the early universe. (aps.org)
  • In particular, the ground state of the two-dimensional Hubbard model, the most intensively studied model for cuprate high temperature superconductors, exhibits a spin density wave instability at a 2 k F vector, at least at weak coupling. (mpg.de)
  • fluctuations
  • Recent work has highlighted remarkable effects of classical thermal fluctuations in the dipolar spin ice compounds, such as "artificial magnetostatics. (case.edu)
  • We find a rich variety of exotic phases: while on the square and checkerboard lattices the ground state exhibits dimer-N\'eel order and plaquette order, respectively, quantum fluctuations on the honeycomb lattice destroy any order, giving rise to a spin-orbital liquid. (perimeterinstitute.ca)
  • But whether the horizon catches light or sound, Hawking-radiation should be produced regardless, and it should appear in form of fluctuations (in the fluid or quantum matter fields, respectively) that are paired across the horizon. (blogspot.com)
  • At low temperature the systems is dominated by strong quantum fluctuations. (cea.fr)
  • In the very low temperature limit the physical properties are determined by quantum fluctuations, which can give rise to new exotic ground states, e.g. the observation of superconductivity close to the point where the magnetic order vanishes. (cea.fr)
  • At the critical point critical spin fluctuations diverge giving rise to a second order phase transition. (cea.fr)
  • found strong infrared divergencies and concluded that fluctuations destroy the quantum critical point (QCP), such that the phase transition is ultimately discontinuous. (mpg.de)
  • helium
  • A professor at Cornell since 1964, he was an authority on liquid helium. (cornell.edu)
  • Much of his work focused on the liquid and solid phases of helium three and four. (cornell.edu)
  • Armed with real-time videos of solid hydrogen particles trapped on quantum vortices in superfluid helium, the Maryland group has been able to observe the lattice motions and capture what may be the first movies of waves in the vortex lattice. (aps.org)
  • Liquid helium, though, is much easier to observe, and when it is cooled below 2.17 Kelvin (colder than deep space), it undergoes a phase transition to a "superfluid" state. (aps.org)
  • Since the vortices are only the width of a helium atom and are therefore nominally invisible, we inject hydrogen gas into the rotating liquid helium. (aps.org)
  • We find that these quantized vortices look like strings of spaghetti that begin and end on the walls of the cryostat, the thermos-like vessel that contains our liquid helium. (aps.org)
  • The chemical potential must reside safely within this gap to avoid detrimental contributions to the edge current from the bulk material, and very low temperatures (below that of liquid helium) are needed to suppress thermal excitation of charge carriers into those bulk electron bands ( 7 , 8 ). (sciencemag.org)
  • superconductivity
  • Minimal evidence of a Higgs transition 1 of north and south poles of electron spins was observed in a magnet Yb2Ti2O7 at the absolute temperature 2 0.21 K. A fractionalization of these monopoles from electron spins was observed on cooling to 0.3 K. On further cooling below 0.21 K, the material showed the ferromagnetism to be understood as a superconductivity of monopoles. (phys.org)
  • correlations
  • This mini-program will focus on quantum materials, models and field theories where strong correlations result in novel emergent phenomena. (perimeterinstitute.ca)
  • We used numerically exact determinant quantum Monte Carlo calculations to demonstrate dynamical stripe correlations in the three-band Hubbard model, which represents the local electronic structure of the copper-oxygen plane. (stanford.edu)
  • Spin correlations remain short ranged, as in the spin-liquid parent state, from which we infer that the state is a crystal of spinless holons, rather than of holes. (stanford.edu)
  • Charge and spin correlations in low dimensional systems are often peaked at 2 k F vectors, such that they are privileged wave vectors for charge and spin density wave instabilities. (mpg.de)
  • Phenomena
  • 1) Exchange Monte Carlo methods have been proposed, and applied to treating slow relaxation processes and have clarified unusual critical phenomena of spin glasses. (go.jp)
  • diagram
  • 5) First principles path-integral molecular dynamics method has been developed to consider quantum effects of light atoms and has given insights on of hydrogen phase diagram under high pressure as well as behaviors of myuonium and hydrogen in solids. (go.jp)
  • Frustration
  • However, a geometrical frustration, which will be explained below, sometimes suppresses a formation of the magnetic order, as in materials called spin ice, Dy2Ti2O7 and Ho2Ti2O7. (phys.org)
  • Because of this frustration, the four spins on each tetrahedron are compromised to form a "2-in, 2-out" structure, as the most stable one (Fig.1, upper right). (phys.org)
  • instabilities
  • The momentum and energy dependences of the 2 k F density fluctuation propagator differs strongly from that for generic incommensurate wave vectors, and also from the one for commensurate (π,π) charge or spin density wave instabilities, for which quantum critical properties have been extensively studied in the past. (mpg.de)
  • systems
  • Ordering emerging from disorder effects in quantum spins, numerical evidence for the existence of chairal spin glass in 3D systems, electron differentiation in the momentum space, and localization of light atoms by quantum zero-point motion. (go.jp)
  • Recently, there has been remarkable progress in the theory of topological phases in strongly correlated systems. (mpg.de)
  • In addition he was interested in classical and quantum spin systems, order and disorder in solids, two-dimensional melting and problems in materials science. (cornell.edu)
  • Quantum spin Hall (QSH) systems are two-dimensional (2D) representatives of the family of topological insulators, which exhibit conduction channels at their edges that are inherently protected against certain types of scattering. (sciencemag.org)
  • Initially predicted for graphene ( 1 , 2 ) and eventually realized in HgTe quantum wells ( 3 , 4 ), in the QSH systems realized so far ( 5 , 6 ), the decisive bottleneck preventing applications is the small bulk energy gap of less than 30 meV. (sciencemag.org)
  • dynamics
  • In this talk, I will address the effects of terms which induce quantum dynamics in a range of models close to the classical spin ice point. (case.edu)
  • For more than fifty years, scientists have worked to observe and understand the dynamics of lattices of quantized vortices, which may be best thought of as long, skinny quantum tornadoes. (aps.org)
  • configurations
  • In a paper appearing in Nature Materials ( 'Selective transformations between nanoparticle superlattices via the reprogramming of DNA-mediated interactions' ), they describe a way to selectively rearrange the nanoparticles in three-dimensional arrays to produce different configurations, or phases, from the same nano-components. (nanowerk.com)
  • Various types of reprogramming strands can be used to selectively trigger the transformation to different phases, or configurations, of the same particle combinations. (nanowerk.com)
  • The right shows Directions and configurations allowed for spins located at vertex points of the unit tetrahedron of the pyrochlore lattice structure. (phys.org)
  • Yet a huge number of spin configurations satisfy the ice rule over the crystal, preventing a spin ordering even at low temperatures. (phys.org)
  • atoms
  • Since this compound does show a long-range magnetic ordering at low temperatures, a new synthesis at 620°C and 2.5 GPa was undertaken in order to obtain a different modification of this phase called 6H-B. In this phase the Ni atoms don't occupy the same layers as in the 6H-A structure but the upper one of the layers that share octahedron faces. (imaging-git.com)
  • The symmetric Kugel-Khomskii can be seen as a minimal model describing the interactions between spin and orbital degrees of freedom in certain transition-metal oxides with orbital degeneracy, and it is equivalent to the SU(4) Heisenberg model of four-color fermionic atoms. (perimeterinstitute.ca)
  • weakly
  • Here we will take the concepts from lecture one and set out to construct from the same Josephson junctions very weakly non-linear circuits which operate as phase-preserving amplifiers. (case.edu)
  • insulators
  • Topological insulators (TIs) are a recently discovered state of matter characterized by an "inverted" band structure driven by strong spin-orbit coupling. (case.edu)
  • antiferromagnetically
  • When spins that interact antiferromagnetically with their neighbors are positioned on a triangular lattice, there is no way that a long range order can satisfy all the interactions. (imaging-git.com)
  • Novel
  • By using these developed algorithms, we have predicted existence of new states of matter, and revealed various novel properties.Examples are, prediction of quantum spin liquid phase near metal-insulator phase boundary. (go.jp)
  • critical exponents
  • We determine directly the order parameter (transverse magnetization), the ordering temperature, the spin structure, and the critical exponents around the transition. (epfl.ch)
  • measurements
  • By combined susceptibility, specific-heat, and 35 Cl nuclear-magnetic-resonance (NMR) measurements, we demonstrate that α-RuCl3 undergoes a quantum phase transition to a QSL in a magnetic field of 7.5 T applied in the ab plane. (aps.org)