Atomic Structures

Effectively Existentially-Atomic Structures

The notions we study in this paper, those of existentially-atomic structure and effectively existentially-atomic structure, are not really new. The objective of this paper is to single them out, survey their properties from a computability-theoretic viewpoint, and prove a few new results about them. These structures are the simplest ones around, and for that reason alone, it is worth analyzing ...

Stability analysis of atomic structures

The stability and failure mechanism of a structure at the nanometer scale are important for understanding the mechanical behavior of nanoscale materials and structures. This thesis focuses on the material stability of atomic structures. First, the material stability of pristine carbon nanotubes is investigated at the continuum level by using the crystal elasticity theory. A homogenized continuu...

Arithmetic Aspects of Atomic Structures

PFfit: Fitting Atomic Structures in 3D EM

Motivation. We develop a new generalized framework for fitting crystal structures into density maps. The framework includes three new scoring functions that quantify the goodness of fit between the crystal structure and density map: (A) the scattering potential score, which is based on using a more realistic representation of the input crystal structure in terms of the density map, (B) the non-...

Dark-line atomic resonances in submillimeter structures.

We present measurements of dark-line resonances excited in cesium atoms confined in submillimeter cells with a buffer gas. The width and contrast of the resonances were measured for cell lengths as low as 100 microm. The measured atomic Q factors are reduced in small cells because of frequent collisions of atoms with the cell walls. However, the contrast of coherent population trapping resonanc...