Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

University of Nebraska - Lincoln

2012

Discipline
Keyword
Publication

Articles 91 - 96 of 96

Full-Text Articles in Physics

Imaging Of Isolated Molecules With Ultrafast Electron Pulses, Christopher J. Hensley, Jie Yang, Martin Centurion Jan 2012

Imaging Of Isolated Molecules With Ultrafast Electron Pulses, Christopher J. Hensley, Jie Yang, Martin Centurion

Martin Centurion Publications

Imaging isolated molecules in three dimensions with atomic resolution is important for elucidating complex molecular structures and intermediate states in molecular dynamics. This goal has so far remained elusive due to the random orientation of molecules in the gas phase. We show that threedimensional structural information can be retrieved from multiple electron diffraction patterns of aligned molecules. The molecules are aligned impulsively with a femtosecond laser pulse and probed with a femtosecond electron pulse two picoseconds later, when the degree of alignment reaches a maximum.


Perpendicular Magnetization In Coo (111) Layers Induced By Exchange Interaction With Ferromagnetic Co And Ni60cu40 Nanoclusters, Damien Le Roy, R. Morel, A. Brenac, S. Pouget, L. Notin Jan 2012

Perpendicular Magnetization In Coo (111) Layers Induced By Exchange Interaction With Ferromagnetic Co And Ni60cu40 Nanoclusters, Damien Le Roy, R. Morel, A. Brenac, S. Pouget, L. Notin

Faculty Publications, Department of Physics and Astronomy

The magnetization reversal of ferromagnetic nanoparticles coupled by exchange with a CoO (111) thin film has been studied. The interfacial exchange interaction triggers the appearance of an out-of-plane magnetization in the CoO (111) film. Co and Ni60Cu40 particles were chosen, as they present an order of magnitude difference in the saturation magnetization and Curie temperatures that surround the Ne´el temperature of CoO. In both cases, the exchange coupling leads to an increase of the coercive field, up to 200% in Co particles, and small exchange bias of 100 Oe when the external magnetic field is applied ...


Tailoring Magnetocrystalline Anisotropy Of Fept By External Strain, Pavel Lukashev, Nathan Horrell, Renat F. Sabirianov Jan 2012

Tailoring Magnetocrystalline Anisotropy Of Fept By External Strain, Pavel Lukashev, Nathan Horrell, Renat F. Sabirianov

Faculty Publications, Department of Physics and Astronomy

We propose using strain assisted reduction in anisotropy of FePt to control magnetization reversal in the writing on the magnetic storage devices. Our first-principles calculations show 21% decrease of the magnetocrystalline anisotropy energy (MAE) with application of 1.5% tensile biaxial strain. The reduction of MAE is primarily due to the change of the c/a ratio and to some extent due to the increase in volume. We propose building bilayer (or heterostructure) of FePt and piezoelectric film. This system is expected to allow the control of anisotropy constant by applying electric field to the system. Finally, we discuss the ...


Controlled Double-Slit Electron Diffraction, Roger Bach, Damian Pope, Sy-Hwang Liou, Herman Batelaan Jan 2012

Controlled Double-Slit Electron Diffraction, Roger Bach, Damian Pope, Sy-Hwang Liou, Herman Batelaan

Faculty Publications, Department of Physics and Astronomy

Double-slit diffraction is a corner stone of quantum mechanics. It illustrates key features of quantum mechanics: interference and the particle-wave duality of matter. In 1965, Richard Feynman presented a thought experiment to show these features. Here we demonstrate the full realization of his famous thought experiment. By placing a movable mask in front of a double-slit to control the transmission through the individual slits, probability distributions for single- and double-slit arrangements were observed. Also, by recording single electron detection events diffracting through a double-slit, a diffraction pattern was built up from individual events.


On The Relation Between The Feynman Paradox And The Aharonov–Bohm Effects, Scot Mcgregor, Ryan Hotovy, Adam Caprez, Herman Batelaan Jan 2012

On The Relation Between The Feynman Paradox And The Aharonov–Bohm Effects, Scot Mcgregor, Ryan Hotovy, Adam Caprez, Herman Batelaan

Faculty Publications, Department of Physics and Astronomy

The magnetic Aharonov–Bohm (A–B) effect occurs when a point charge interacts with a line of magnetic flux, while its reciprocal, the Aharonov–Casher (A–C) effect, occurs when a magnetic moment interacts with a line of charge. For the two interacting parts of these physical systems, the equations of motion are discussed in this paper. The generally accepted claim is that both parts of these systems do not accelerate, while Boyer has claimed that both parts of these systems do accelerate. Using the Euler–Lagrange equations we predict that in the case of unconstrained motion, only one part ...


Dynamics Underlying The Gaussian Distribution Of The Classical Harmonic Oscillator In Zero-Point Radiation, Wayne Cheng-Wei Huang, Herman Batelaan Jan 2012

Dynamics Underlying The Gaussian Distribution Of The Classical Harmonic Oscillator In Zero-Point Radiation, Wayne Cheng-Wei Huang, Herman Batelaan

Faculty Publications, Department of Physics and Astronomy

No abstract provided.