Diffraction and interference of matter waves are key phenomena in quantum mechanics. Here we present some results on particle diffraction a wide variety situations, ranging from simple slit experiments to more complicated cases such as atom scattering by corrugated metal surfaces with isolated adsorbates. The principal novelty our study is the use so-called Bohmian formalism trajectories. These trajectories able satisfactorily reproduce main features experimental and, importantly, they...

Interference is one of the most fundamental features which characterizes quantum systems. Here we provide an exhaustive analysis interfere dynamics associated with wave-packet superpositions from both standard quantum-mechanical perspective and Bohmian one. From this analysis, clear insightful pictures physics involved in kind processes are obtained, general validity (i.e., regardless type wave packets considered) understanding more complex cases where interference crucial (e.g., scattering...

The quantum Cramér-Rao bound (QCRB) stands as a cornerstone of metrology. Yet, akin to its classical counterpart, it provides only local information and overlooks higher-order details. We leverage the theory asymptotics circumvent these issues, providing corrections performance estimators beyond QCRB. While QCRB often yields whole family optimal states several measurements, our approach allows us identify measurements within that are otherwise equivalent according alone; requisite for...

The method of quantum trajectories proposed by de Broglie and Bohm is applied to the study atom diffraction surfaces. As an example, a realistic model for scattering He off corrugated Cu considered. In this way, final angular distribution obtained box counting, which in excellent agreement with results calculated standard $S$ matrix methods theory. More interestingly, accumulation at different peaks explained terms corresponding potential. This nonlocal potential ``guides'' causing...

A well-known phenomenon in both optics and quantum mechanics is the so-called Talbot effect. This near field interference effect arises when infinitely periodic diffracting structures or gratings are illuminated by highly coherent light particle beams. Typical diffraction patterns known as carpets then observed. Here authors provide an insightful picture of this nonlocal well its classical limit terms Bohmian mechanics, also showing causal reasons conditions that explain appearance. As...

The scattering of He atoms from adsorbed CO molecules on the Pt(111) surface is described within formalism quantum trajectories provided by Bohmian mechanics. We show that main mechanism leading to formation rainbows and resonance enhanced trapping vortices.

In this work, a full quantum study of the scattering He atoms off single CO molecules, adsorbed onto Pt(111) surface, is presented within formalism trajectories provided by Bohmian mechanics. By means theory, it shown that underlying dynamics strongly dominated existence transient vortitial trapping with measurable effects on whole diffraction pattern. This kind emphasizes key role played vortices in scattering. Moreover, an analysis surface rainbow effect caused local corrugation molecule...

Wave-packet interference is investigated within the complex quantum Hamilton-Jacobi formalism using a hydrodynamic description. Quantum leads to formation of topological structure caves in space-time Argand plots. These consist vortical and stagnation tubes originating from isosurfaces amplitude wave function its first derivative. Complex trajectories display counterclockwise helical wrapping around hyperbolic deflection near tubes. The string alternating sufficient generate divergent...

We introduce a pedagogical discussion on Bohmian mechanics and its physical implications in connection with the important role played by quantum phase dynamics of processes. In particular, we focus phenomena such as coherence, diffraction, interference, due to their historical relevance development theory key myriad fundamental applied problems current interest.

The experimental line shape broadening observed in adsorbate diffusion on metal surfaces with increasing coverage is usually related to the nature of adsorbate-adsorbate interaction. Here we show that this can also be understood terms a fully stochastic model just considering two noise sources: (i) Gaussian white accounting for surface friction, and (ii) shot replacing physical interaction potential. Furthermore, contrary what could expected, relatively weak adsorbate-substrate interactions...

Young's two-slit experiment constitutes the paradigm of quantum complementarity. According to complementarity principle, complementary aspects systems cannot be measured at same time by experiment. This has been a long debate in mechanics since its inception. But is this true constraint? In 2011, an astounding realization showed that perhaps not case, and boundaries our understanding world are still far away.

The Schrödinger equation admits smooth and finite solutions that spontaneously evolve into a singularity, even for free particle. This blowup is generally ascribed to the intrinsic dispersive character of associated time evolution. We resort notion quantum Bohmian trajectories relate this singular behavior local phase variations, which generate an underlying velocity field responsible driving flux toward region.

This work investigated the premature failure of a beam reinforcement made austenitic stainless steel AISI 310 used in entrance rolling furnace working continuously at cycles from 650 to 850 °C. Fracture surface and microstructural investigations allowed identify fracture mechanism as fatigue failure. The was probably initiated oxidized grain boundaries an early stage service life, when no microstructure degradation present, while most crack propagation occurred after precipitation secondary...