Noncontact atomic force microscopy (NC-AFM) is being increasingly used to measure the interaction force between an atomically sharp probe tip and surfaces of interest, as a function of the three spatial dimensions, with picometer and piconewton accuracy. Since the results of such measurements may be affected by piezo nonlinearities, thermal and electronic drift, tip asymmetries, and elastic def...

Crystallography, the primary method for determining the 3D atomic positions in crystals, has been fundamental to the development of many fields of science. However, the atomic positions obtained from crystallography represent a global average of many unit cells in a crystal. Here, we report, for the first time, the determination of the 3D coordinates of thousands of individual atoms and a point...

This article has no abstract.

Let h(a1 , •.. , an) denote the harmonic mean n(a1 1 + ... +a; 1) -1 of positive num­ bers a1 , ••. , all' and extend this definition (by continuity) to the non-negative case by setting h(a l' ... , an) = 0 if ai = 0 for some i ~ n. Recall that a measure J1. is non-atomic if every measurable set A of strictly positive measure has a measur­ able subset B ~ A satisfying J1.(A) > J1.(B) > O. A mea...

In an effort to measure electron-impact ionization (EII) cross-sections of He-like Fe24+ at the electron beam ion trap (EBIT) facility National Institute Standards and Technology (NIST), we have experimentally determined corrections nominal energy by voltages applied EBIT. High-resolution X-ray spectra were recorded energies between 6660 eV 6750 using microcalorimetry based upon array 192 trans...

background: nickel is an important constituents widely used in different industrial processes for production of various syn¬thetic materials. for evaluation of workers’ exposure to trace toxic metal of ni (ii), environmental and biological monitor¬ing are essential processes, in which, preparation of samples is one of the most time-consuming and error-prone as¬pects prior to analysis. methods: ...

The development of methods for completely determining the quantum state of an atom or cavity field @1# continues to be an important issue in atomic physics. For example, in the field of quantum optics, schemes have been recently proposed, based on the Stem-Gerlach effect, for completely determining the quantum state of an atom as a way of fully characterizing the quantized electromagnetic field...

In a typical atomic interferometer, the atomic wavepacket is split first by what can be considered effectively as an atomic beamsplitter. The split components are then redirected towards each other by atomic mirrors. Finally, the converging components are recombined by another atomic beam splitter. Here, we demonstrate a novel atomic interferometer where the atomic split is split and recmobined...

We study possible scenarios for quantum non-demolition measurements using Bose-Einstein condensates. We show that the interactions between condensate atoms makes it possible to measure the atom number with minimal back action on the system. This is an example of atomic nonlinear optics that has significant implications in the quantum state preparation of the Bose condensates. Typeset using REVT...