Anomalous Transport Induced by Non-Hermitian Anomalous Berry Connection in Non-Hermitian Systems

Non-Hermitian materials can exhibit not only exotic energy band structures but also an anomalous velocity induced by non-Hermitian anomalous Berry connection as predicted by the semiclassical equations of motion for Bloch electrons. However, it is unclear how the modified semiclassical dynamics modifies transport phenomena.Here, we theoretically demonstrate the emergence of anomalous oscillations driven by either an external dc or ac electric field, which arise from non-Hermitian anomalous Berry...     

Anomalous Energy Minima Surfaces

Previous publications^2–5 have examined the phenomenon of level crossings as predicted by the semiempirical techniques CNDO/2⁶, IMDO⁷, and MINDO/3⁸ for certain molecules when the total energy is viewed as a function of some conformational property. The purpose of this article is to examine this same phenomenon using the extended Hückel method(EHM)⁹, the iterated extended Hückel method(IEHM), and an ab-initio procedure with a minimal STO-3G basis set. The molecule chosen for this study is CO₂ due to its structural simplicity and since previous calculations^2–5 have demonstrated level crossing with this molecule.     

CUPID-0: the first array of enriched scintillating bolometers for 0$$\nu \beta \beta $$ decay investigations

The CUPID-0 detector hosted at the Laboratori Nazionali del Gran Sasso, Italy, is the first large array of enriched scintillating cryogenic detectors for the investigation of \(^{82}\)Se neutrinoless double-beta decay (\(0\nu \beta \beta \)). CUPID-0 aims at measuring a background index in the region of interest (RoI) for \(0\nu \beta \beta \) at the level of 10\(^{-3}\) counts/(keV kg years), the lowest value ever measured using cryogenic detectors. CUPID-0 operates an array of Zn\(^{82}\)Se scintillating bolometers coupled with bolometric light detectors, with a state of the art technology for background suppression and thorough protocols and procedures for the detector preparation and construction. In this paper, the different phases of the detector design and construction will be presented, from the material selection (for the absorber production) to the new and innovative detector structure. The successful construction of the detector lead to promising preliminary detector performance which is discussed here.     

Anomalous $\eta/\eta^\prime$ decays: the triangle and box anomalies

We examine the decay modes within the context of the hidden local symmetry (HLS) model. Using numerical information derived in previous fits to the and Ve ⁺ e ^- decay modes in isolation and the lineshape determined in a previous fit to the pion form factor, we show that all aspects of these decays can be predicted with fair accuracy. Freeing some parameters does not improve the picture. This is interpreted as strong evidence in favor of the box anomaly in the decays, which occurs at precisely the level expected. We also construct the set of equations defining the amplitudes for and at the chiral limit, as predicted from the anomalous HLS Lagrangian appropriately broken. This provides a set of four equations depending on only one parameter, instead of three for the traditional set. This is also shown to match the (two-angle, two-decay-constant) - mixing scheme recently proposed and is also fairly well fulfilled by the data. The information returned from the fits also matches expectations from previously published fits to the decay modes in isolation.Received: 29 June 2003, Revised: 17 September 2003, Published online: 4 November 2003     

Energy degradation effect in\bar pAannihilation

Energy degradation effect on \(\bar pA\) annihilation probability is investigated in the framework of a model with the successive collisions of the leading cluster. This is to introduce the slow-down of the cluster to usual Glauber's multiple collision model. The annihilation probability is found to be sensitive to the elasticity of the leading cluster for heavy nuclei such asPb even at high energies around 200 GeV.     

A multi-isotope $$0\nu 2\beta $$ bolometric experiment

There are valuable arguments to perform neutrinoless double beta (\(0\nu 2\beta \)) decay experiments with several nuclei: the uncertainty of nuclear-matrix-element calculations; the possibility to test these calculations by using the ratio of the measured lifetimes; the unpredictability of possible breakthroughs in the detection technique; the difficulty to foresee background in \(0\nu 2\beta \) decay searches; the limited amount of isotopically enriched materials. We propose therefore approaches to estimate the Majorana neutrino mass by combining experimental data collected with different \(0\nu 2\beta \) decay candidates. In particular, we apply our methods to a next-generation experiment based on scintillating and Cherenkov-radiation bolometers. Current results indicate that this technology can effectively study up to four different isotopes simultaneously (\(^{82}\)Se, \(^{100}\)Mo, \(^{116}\)Cd and \(^{130}\)Te), embedded in detectors which share the same concepts and environment. We show that the combined information on the Majorana neutrino mass extracted from a multi-candidate bolometric experiment is competitive with that achievable with a single isotope, once that the cryogenic experimental volume is fixed. The remarkable conceptual and technical advantages of a multi-isotope investigation are discussed. This approach can be naturally applied to the proposed CUPID project, follow-up of the CUORE experiment that is currently taking data in the Gran Sasso underground laboratory.     

The Interpolating Airy Kernels for the \beta =1 and \beta =4 Elliptic Ginibre Ensembles

We consider two families of non-Hermitian Gaussian random matrices, namely the elliptic Ginibre ensembles of asymmetric $N$ -by- $N$ matrices with Dyson index $\beta =1$ (real elements) and with $\beta =4$ (quaternion-real elements). Both ensembles have already been solved for finite $N$ using the method of skew-orthogonal polynomials, given for these particular ensembles in terms of Hermite polynomials in the complex plane. In this paper we investigate the microscopic weakly non-Hermitian large- $N$ limit of each ensemble in the vicinity of the largest or smallest real eigenvalue. Specifically, we derive the limiting matrix-kernels for each case, from which all the eigenvalue correlation functions can be determined. We call these new kernels the “interpolating” Airy kernels, since we can recover—as opposing limiting cases—not only the well-known Airy kernels for the Hermitian ensembles, but also the complementary error function and Poisson kernels for the maximally non-Hermitian ensembles at the edge of the spectrum. Together with the known interpolating Airy kernel for $\beta =2$ , which we rederive here as well, this completes the analysis of all three elliptic Ginibre ensembles in the microscopic scaling limit at the spectral edge.     

Reduced Two-Field Equations and Anomalous Transport Scaling in Low-Temperature Plasmas

After a review of more or less systematic approaches for normal as well as anomalous particle transport phenomena across a magnetic field, simplified macroscopic models are discussed. A reduced two-field model for collision-dominated low-temperature plasmas is presented. Although it looks similar to its high-temperature analogue (known as the Hasegawa-Wakatani equations), it has significant peculiarities which are discussed in detail. Some basic results following from the reduced two-field model, e.g. anomalous transport scaling close to the onset of collisional driftwave instability, are discussed.     

Energy Transport in Weakly Anharmonic Chains

We investigate the energy transport in a one-dimensional lattice of oscillators with a harmonic nearest neighbor coupling and a harmonic plus quartic on-site potential. As numerically observed for particular coupling parameters before, and confirmed by our study, such chains satisfy Fourier’s law: a chain of length N coupled to thermal reservoirs at both ends has an average steady state energy current proportional to 1/N. On the theoretical level we employ the Peierls transport equation for phonons and note that beyond a mere exchange of labels it admits nondegenerate phonon collisions. These collisions are responsible for a finite heat conductivity. The predictions of kinetic theory are compared with molecular dynamics simulations. In the range of weak anharmonicity, respectively low temperatures, reasonable agreement is observed.     

Instationary Electric Fields,Ion Transport and Strong Density Fluctuations in Tokamaks with Dominant Anomalous Electron Transport

A common explanation is given for ion transport and strong broadband density fluctuations in tokamaks as a result of large anomalous electron transport near dominant magnetic surfaces (resp. in small magnetic islands). The main mechanism is local density flattening connected with an anomalous electron transport induced instationary radial electric field, which forces the ions via polarization drift to follow the electrons. For the density flattening process an exact solution of the time-dependent diffusion equation for a linear initial profile over the island width is used. From this we also derive an expression for a temporal growing radial electric field. This positive field reaches its maximum at the density plateau. Strong viscous diffusion or instability-induced transport between high and low electric field regions may now reverse the density flattening. Therefore relaxation oscillations result which may also explain the observed strong density and potential fluctuations in tokamaks. Several details of recent measurements of impurity ion behaviour and density fluctuations in tokamaks may be better explained with the theory given here.     

Energy Transport Through Rare Collisions

We study a one-dimensional Hamiltonian chain of masses perturbed by an energy conserving noise. The dynamics is such that, according to its Hamiltonian part, particles move freely in cells and interact with their neighbors through collisions, made possible by a small overlap of size ϵ>0 between near cells. The noise only randomly flips the velocity of the particles. If ϵ→0, and if time is rescaled by a factor 1/ϵ, we show that energy evolves autonomously according to a stochastic equation, which hydrodynamic limit is known in some cases. In particular, if only two different energies are present, the limiting process coincides with the simple symmetric exclusion process.     

Simple Systems with Anomalous Dissipation and Energy Cascade

We analyze a class of dynamical systems of the type where f _n (t) is a forcing term with only for and the coupling coefficients c _n satisfy a condition ensuring the formal conservation of energy . Despite being formally conservative, we show that these dynamical systems support dissipative solutions (suitably defined) and, as a result, may admit unique (statistical) steady states when the forcing term f _n (t) is nonzero. This claim is demonstrated via the complete characterization of the solutions of the system above for specific choices of the coupling coefficients c _n . The mechanism of anomalous dissipations is shown to arise via a cascade of the energy towards the modes with higher n; this is responsible for solutions with interesting energy spectra, namely scales as as n→∞. Here the exponents α depend on the coupling coefficients c _n and denotes expectation with respect to the equilibrium measure. This is reminiscent of the conjectured properties of the solutions of the Navier-Stokes equations in the inviscid limit and their accepted relationship with fully developed turbulence. Hence, these simple models illustrate some of the heuristic ideas that have been advanced to characterize turbulence, similar in that respect to the random passive scalar or random Burgers equation, but even simpler and fully solvable.     

Anomalous Energy Minima Studies by Mindo/3

A previous publication¹ utilizing the INDO² and CND0/2³ semi-empirical SCF-MO techniques has shown that these methods predict anomalous minima in the potential surfaces of small molecules and molecular ions, particularly those of type 0-X-0. Two studies have bcmen published concerning the removal of such anomalous pre-dictiors. The first approach⁴ involved reparameterization of the INDO method – specifically involving the Slater exponents α, and the bonding parameters B° of carbon and oxygen – to remove the anomalous iinimum from the potential surface of C0₂. It was de-monstrated that reparameterization could be used to remove the Salse minimum in this case; but only at the expense of the other predictive qualities of INDO, or with the prediction of an unreal-istically broad energy minimum – neither of which could b e con-sidered an acceptable solution.     

Anomalous Transport Characteristics of High Temperature Superconductors and Josephson Currents

The transport characteristics of high temperature superconductor current and Josephson current is inves-tigated in the framework of the modified time-dependent Ginzburg-Landau model and the Lawrence-Doniach model.We evaluated the vortex equation and found that the signs of the high temperature superconductor current and theJosephson current can reverse. Some explicit expressions for different cases are derived, which accord with experimentaldata.     

Anomalous Dissipation and Energy Cascade in 3D Inviscid Flows

Adopting the setting for the study of existence and scale locality of the energy cascade in 3D viscous flows in physical space recently introduced by the authors to 3D inviscid flows, it is shown that the anomalous dissipation is – in the case of decaying turbulence – indeed capable of triggering the cascade which then continues ad infinitum, confirming Onsager’s predictions.     

Asymptotic Properties of the Density of Particles in $$\beta $$-Ensembles

We extend recent results on the asymptotic equipartition property for the density of n particles in \(\beta \)-ensembles, as n tends to infinity. We prove the large deviation principle of the log-density for a general potential and the mod-Gaussian convergence in the classical examples.