Due to Klein tunneling, electrostatic potentials are unable confine Dirac electrons. We show that it is possible massless fermions in a monolayer graphene sheet by inhomogeneous magnetic fields. This allows one design mesoscopic structures barriers, e.g. quantum dots or point contacts.

We study the behavior of charge carriers in graphene inhomogeneous perpendicular magnetic fields. consider two types one-dimensional profiles, uniform one direction: a sequence $N$ barriers and alternating wells. In both cases, we compute transmission coefficient structure by means transfer-matrix formalism associated conductance. first case becomes increasingly transparent upon increasing at fixed total flux. second find strong wave-vector filtering resonant effects. also calculate band...

We consider the Kitaev chain model with finite and infinite range in hopping pairing parameters, looking particular at appearance of Majorana zero energy modes massive edge modes. study system both presence absence time reversal symmetry, by means topological invariants exact diagonalization, disclosing very rich phase diagrams. In particular, for extended terms, we can get as many each end neighbors involved couplings. Finally generalize transfer matrix approach useful to calculate...

A metallic electron system near an orientational symmetry breaking Pomeranchuk instability is characterized by a ''soft'' Fermi surface with enhanced collective fluctuations. We analyze fluctuation effects in two-dimensional on square lattice the vicinity of d-wave symmetry, using phenomenological model which includes interactions small momentum transfer only. compute dynamical density correlations form factor for momenta and frequencies, effective interaction due to exchange, self-energy....

We consider electron waveguides (quantum wires) in graphene created by suitable inhomogeneous magnetic fields. The properties of unidirectional snake states are discussed. For a certain field profile, two spatially separated counterpropagating formed, leading to conductance quantization insensitive backscattering impurities or irregularities the field.

We study the localization transitions for coupled one-dimensional lattices with quasiperiodic potential. In addition to localized and extended phases, there is an intermediate mixed phase that can be easily explained decoupling system so as deal effective uncoupled Aubry-Andr\'e chains different transition points. clarify, therefore, origin of such phase, finding conditions getting a uniquely defined mobility edge systems. Finally, we consider many energy shift compose extension model in two...

We study a simple realistic model for describing the diffusion of an infectious disease on population individuals. The dynamics is governed by single functional delay differential equation, which, in case large population, can be solved exactly, even presence time-dependent infection rate. This has higher degree accuracy than that so-called SIR model, commonly used epidemiology, instead, formulated terms ordinary equations. apply this to describe outbreak new disease, Covid-19, Italy, taking...

Work extraction in quantum finite systems is an important issue thermodynamics. The optimal work extracted called ergotropy, and it achieved by maximizing the average over all unitary cycles. However, agent that non-neutral to risk affected fluctuations should extract following expected utility hypothesis. Thus, we investigate performed a function We mainly focus on initial states are incoherent with respect energy basis, achieving probability distribution of work. In this case show how will...

We study the spin-resolved transport through magnetic nanostructures in monolayer and bilayer graphene. take into account both orbital effect of inhomogeneous perpendicular field as well in-plane spin splitting due to Zeeman interaction exchange coupling possibly induced by proximity a ferromagnetic insulator. find that single barrier exhibits wave-vector-dependent filtering at energies close transmission threshold. This is significantly enhanced resonant double configuration, where...

We compute the ground-state correlation functions of an exactly solvable chain integer spins, recently introduced in [R. Movassagh and P. W. Shor, arXiv:1408.1657], whose ground state can be expressed terms a uniform superposition all colored Motzkin paths. Our analytical results show that for spin $s\ensuremath{\ge}2$ there is violation cluster decomposition property. This has to contrasted with $s=1$, where property holds. Correspondingly, $s=1$ one gets light-cone profile propagation...

A complete understanding of the statistics work done by quenching a parameter quantum many-body system is still lacking in presence an initial coherence energy basis. In this case, can be represented class quasiprobability distributions. Here, we try to clarify genuinely features process studying for Ising model transverse field. We consider both global and local quench focusing mainly on thermodynamic limit. find that, while there symmetric noncontextual representation with Gaussian...

Abstract Background The prevention of invasive fungal infections (IFIs) is crucial for paediatric haemato-oncological patients. This study evaluates the clinical efficacy and side-effects posaconazole liposomal amphotericin B (L-AmB) as primary prophylaxis. Materials methods cohort included patients aged 3 months to 21 years who received or L-AmB (5 mg/kg twice weekly) prophylaxis from January 2017 March 2022 at Hemato-oncological Pediatric Unit, University Hospital Padua, Italy. Outcomes...

We study the transport properties of a quantum dot contacted to two superconducting reservoirs by means Keldysh field theory approach. determine direct current occurring at equilibrium and electric thermoelectric currents triggered when system is driven out voltage or temperature bias, also for normal-quantum dot-superconductor junction. In particular, we derive present first time explicit expression in superconductor-quantum junction any values difference between leads. show that linear...

We analyze the dc charge transport in quantum critical regime near a d-wave Pomeranchuk instability two dimensions. The decay rate is linear temperature everywhere on Fermi surface except at cold spots Brillouin zone diagonal. For pure systems, this leads to resistivity proportional T(3/2) low-temperature limit. In presence of impurities residual impurity resistance T=0 approached linearly low temperatures.

We study the band structure of graphene's Dirac-Weyl quasiparticles in a one-dimensional magnetic superlattice formed by periodic sequence alternating barriers. The spectrum and nature states strongly depend on conserved longitudinal momentum barrier width. At center Brillouin zone we find new Dirac points at finite energies where dispersion is highly anisotropic, contrast to close neutrality point which remains isotropic. This finding suggests possibility collimating tuning doping.

We study the effects of laser-induced Rashba-like spin-orbit coupling along Bardeen-Cooper-Schrieffer--Bose-Einstein condensate (BCS-BEC) crossover a Feshbach resonance for two-spin-component Fermi gas. calculate fraction in three and two dimensions find that this quantity characterizes better than other quantities, like chemical potential or pairing gap. By considering both singlet triplet pairings, we show large-enough interaction enhances BCS side while suppressing it on BEC side.

We consider an ultracold bosonic binary mixture confined in a one-dimensional double-well trap. The two components are assumed to be hyperfine internal states of the same atom. suppose that these spin-orbit coupled between each other. employ two-mode approximation starting from Gross-Pitaevskii equations and derive system ordinary differential governing temporal evolution inter-well population imbalance component species. study Josephson oscillations Bose-Einstein condensates by analyzing...

The concept of inner friction, by which a quantum heat engine is unable to follow adiabatically its strokes and thus dissipates useful energy, illustrated in an exact physical model where the working substance consists ensemble misaligned spins interacting with magnetic field performing Otto cycle. effect this static disorder under finite-time cycle gives new perspective friction realistic settings. We investigate efficiency power relate performance amount from misalignment temperature...

We analyze the properties of edge states one-dimensional Kitaev model with long-range anisotropic pairing and tunneling. Tunneling are assumed to decay algebraically exponents $\ensuremath{\alpha}$ $\ensuremath{\beta}$, respectively, $\ensuremath{\alpha},\ensuremath{\beta}>1$. determine analytically modes. show that is exponential for $\ensuremath{\alpha}=\ensuremath{\beta}$ when coefficients scaling tunneling terms equal. Otherwise, at sufficiently short distances then algebraic...

Abstract The out-of-plane optical constants of monolayer two-dimensional materials have proven to be experimentally elusive. Owing their reduced dimensionality, measurements limited sensitivity these properties which are hidden by the response substrate. Therefore, there remains an absence scientific consensus on how correctly model crystals. Here we perform experiment a single-layer crystal that addresses problems. We successfully remove substrate contribution its step deposition inside...

The equilibrium Josephson current through a nanoscale multilevel quantum dot with Rashba or Dresselhaus spin-orbit coupling $\ensuremath{\alpha}$ has been computed. critical can be drastically modified already by moderate $\ensuremath{\alpha}$. In the presence of Zeeman field, Datta-Das-like oscillatory dependencies on are predicted.

We formalize the appearance of new types insulators in long-range (LR) fermionic systems. These phases are not included "ten-fold way classification" (TWC) for short-range (SR) topological insulators. This conclusion is obtained studying at first specific one-dimensional LR examples, particular their phase diagrams and contents symmetries entanglement. The purely (LRP) signaled by violation area-law Von Neumann entropy corresponding peculiar distributions entanglement spectrum (ES). origin...

We investigate the use of variational wave-functions that mimic stochastic recurrent neural networks, specifically, unrestricted Boltzmann machines, as guiding functions in projective quantum Monte Carlo (PQMC) simulations spin models. As a preliminary step, we accuracy such network states Ans\"atze for ground state ferromagnetic Ising chain. find by optimizing just three parameters, independently on system size, accurate ground-state energies are obtained, comparable to those previously...