Muhammad Arif

Followers

Following

Public Views

Interests

Uploads

Papers by Muhammad Arif

Application of neutron interferometry to the measurement of thin film density

Applied Physics Letters, 1999

The application of neutron interferometry to the measurement of the atom density of polymer thin ... more The application of neutron interferometry to the measurement of the atom density of polymer thin films ͑Ͻ1 m thick͒ supported on silicon substrates is described. Polymer films were chosen primarily for their fixed, well-defined stoichiometry; however, the technique is applicable to films of any elemental composition. The wavelength-independent phase shift of a beam of thermal neutrons passing through the sample gives a measure of the product of the film atom density, the film thickness, the lattice spacing of the silicon interferometer, and the scattering lengths of the constituent elements of the film. The film thickness was found by x-ray reflectivity while the other two parameters are well-defined quantities. The technique does not rely on complex mathematical modeling of physical processes nor on thin film standards for data interpretation. With some refinements, neutron interferometry is envisioned as an important tool in the creation of thin films having well-defined densities which will be useful in the calibration of many analysis techniques.

Download

The fundamental neutron physics facilities at NIST

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2005

The National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR) is a... more The National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR) is a national center that provides thermal and cold neutrons beams for activities such as materials science, biological, polymer, and fundamental physics research. Four beams are currently in use for fundamental physics experiments. These include a neutron optics and interferometry facility, a 0.496 nm monochromatic beam, a 0.89 nm monochromatic beam, and a high-intensity polychromatic beam. Experiments primarily focus on studies of the weak interaction using neutrons. This paper provides a general overview of the facilities and highlights some current experiments.

Download

Muhammad Arif

Uploads

Papers by Muhammad Arif

Log In