X-ray absorption fine structure (XAFS) has developed into a powerful probe of atomic structure, thermodynamic properties, and anharmonic effects in atomic vibration
of substances [1-28].
A type of atomic vibration
never before seen in ordinary solid materials has been observed in uranium.
His project will use theoretical techniques and artificial intelligence to understand atomic vibrations
called phonons to optimize heat flow in materials on the atomic level.
These light bursts excite atomic vibrations
to very large amplitudes, where their response to the driving electric field becomes nonlinear and conventional description fails to predict their behaviour.
Their analysis revealed that the atomic vibrations
in the crystal lattice were too sluggish to transmit much heat.
The team used Raman spectroscopy to measure the atomic vibrations
throughout a microscopic fossil of a protist, at a sub-micron resolution, and then analyzed the resulting spectra using their new analytic technique.
The author explores crystal structure and crystal diffraction, crystal binding and elastic constants, atomic vibrations
and lattice specific heat, free electrons theory and simple metals, and many other related subjects.
"When you touch an object and it feels 'hot' you are literally sensing the 'buzzing' of the atomic vibrations
. The new definition directly links the unit of temperature to this basic physical reality."
But when it does, it's less likely to set another electron free than it is to create atomic vibrations
that squander the electron's excess energy on heat.
The laser, working together with an external light source, makes use of the natural I atomic vibrations
in silicon to amplify the pump-light as it passes through the chip.
Scientists at the NIST Center for Neutron Research (NCNR) and Brookhaven National Lab have an ongoing collaborative program to study the lattice dynamics (atomic vibrations
) in the PZN and PMN relaxor compounds.
For instance, "the comparison of protein structures at ultra-cold versus room temperature allows the details of atomic vibrations
to be separated from structural disorders," says Helliwell.