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RESEARCHERS STUDY SUPERCONDUCTIVITY, MAGNETISM IN NOVEL MATERIAL
Posted on Thursday, March 01, 2007 @ 23:01:04 UTC by vlad
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 A University of Arkansas physics professor and his colleagues have
created a nanoscale structure that contains both magnetic and
superconducting properties at the same time, and they will be exploring
the properties of this novel material this summer in Switzerland.
Jacques Chakhalian and his colleagues at the Max Planck Institute in
Germany and the University of Grenoble and the National Center for
Scientific Research, both in France, have been awarded research time
and financial support over the next two years at Swiss Light Source at
the Paul Scherrer Institut – the most advanced synchrotron light source
in the world. In 2006, they published a paper in Nature Physics
documenting novel properties at the interface between a superconductor,
known as YBCO, and a ferromagnet, known as LCMO. Their results showed
an interplay between ferromagnetism and superconductivity that had
never been documented before.
“Typically, ferromagnetism destroys superconductivity,” Chakhalian
said. The group’s technique, which allows scientists to combine these
two properties in one thin-film superlattice, opens up a new area of
physics and paves the way for discovering more materials with novel
properties.
To create the lattice, the researchers take a powdered pallet of
the material and use a powerful ultraviolet laser to vaporize the
crystals and deposit them as a multilayer, ultra-thin film on a
substrate. This way they can create one atomic layer at a time.
“You can make it as thin as you want,” Chakhalian said. To find out
more about the unique properties of the superconductor/ferromagnet
material, the research group wants to look at the interface between the
two materials. They plan to do this using the synchrotron at Swiss
Light Source.
The synchrotron light is electromagnetic radiation of varying
wavelengths that can be tuned to a specific wavelength for a particular
experiment. The spectrum at Swiss Light Source varies from infrared
light to soft and hard X-rays. Unlike conventional X-rays, which
diffuse through space, the synchrotron light beams are sharply focused
like a laser beam. This will allow Chakhalian and his colleagues to
study the magnetic and superconducting properties at the interface of
this nanoscale material.
“The main technical challenge is to focus the beam of low energy
photons into a spot the size of a few hundred microns,” Chakhalian
said. Only a few facilities in the world, like Swiss Light Source, have
the technology to create the “soft” X-rays necessary to analyze the
electronic properties of the superconductors and ferromagnets.
The team will conduct their experiment at Swiss Light Source
starting June 18. They will have seven days to complete the first phase
of the research. The award will allow them to return to use the
synchrotron again more than once over the next two years. In the
meantime, they will be busy working with the results of their first
experiments. This project provides a perfect training ground for
University of Arkansas graduate students who are interested in
nanoscience and nanotechnology
“It takes a lot of intellectual effort to analyze the data,” Chakhalian said.
Chakhalian is an assistant professor of physics in the J. William
Fulbright College of Arts and Sciences. In addition to working at the
Swiss Light Source, he also works at the Advanced Photon Source,
Argonne National Laboratories and the ANKA Synchrotron Light Source in
Germany.
Source: University of Arkansas, Fayetteville
Via: http://www.physorg.com/news91974487.html
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Re: RESEARCHERS STUDY SUPEQUANTUM EFFECTS MAKE THE DIFFERENCE (Score: 1)
by vlad on Thursday, March 01, 2007 @ 23:03:23 UTC
(User Info | Send a Message) http://www.zpenergy.com | The atomic constituents of matter are never still, even at absolute zero. This
consequence of quantum mechanics can result in continuous transition between
different material states. Physicists at the Max Planck Institute for Chemical
Physics of Solids have studied this phenomenon using ytterbium, rhodium and
silicon at very low temperatures under the varying influence of a magnetic
field.
Full story at http://www.physorg.com/news91981804.html [www.physorg.com]
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Manipulating the Vacuum Scalar Field with Superconductors (Score: 1)
by vlad on Monday, March 26, 2007 @ 21:31:10 UTC
(User Info | Send a Message) http://www.zpenergy.com | On Mar 26, 2007, at 11:09 AM, art wagner wrote:
Jack, I
just came across this & thought you should at least be aware
of it...
Manipulating the Vacuum Scalar Field with Superconductors [adsabs.harvard.edu]
Smithsonian/NASA ADS Physics
Abstract Service
Authors: Robertson, Glen A.
Affiliation: Gravi Atomi Research, Madison, AL 35757gravi_atomicathotmail.com gravi_atomicathotmail.com
Publication: SPACE TECHNOLOGY AND APPLICATIONS INT.FORUM-STAIF 2005: Conf.Thermophys in Micrograv;
Publication Date: 02/2005
Origin: AIP
Keywords: aerospace propulsion, superconducting materials, space research, gravitational waves, Ginzburg-Landau theory
Abstract Copyright: (c) 2005: American Institute of Physics
DOI: 10.1063/1.1867267
Bibliographic Code: 2005AIPC..746.1371R
Abstract: Many theoretical papers refer to the need to create exotic materials with average negative energies for the formation of space propulsion anomalies such as ``wormholes'' and ``warp drives.'' However, little hope is given for the existence of such material to resolve its creation. Non-minimally coupled scalar fields to gravity appear to be the current direction mathematically. Here, the Ginzburg-Landau (GL) scalar field associated with the type II superconductor is discussed as a medium for producing interactions among energy fluctuations, cosmological scalar fields, and gravity during rapid phase transition on a scale of laboratory apparatus. The study of GL fields in superconductor could possibly lead to a source for generating exotic material. An underlying objective of this paper is to show that the approach to new space propulsion engine cycles based on gravitational disturbances cross many scientific boundaries; cosmology, high energy physics, and superconductivity to name a few. These scientific communities are separate and independent, which suggests that a new area within the science community needs to be established before applicable experimentation can creditably proceed.
------------
From: Jack Sarfatti
To: Sarfatti_Physics_Seminars
Thanks. Tony Robertson makes the same "error" that Eric Davis makes. I mean the remark about "negative energy". Although the physics below is very elementary almost everyone in exotic propulsion does not seem to know it.
Here is the way general relativity really works on this issue.
The equivalence principle for the local mutable dynamical gauging of the universal rigid nondynamical global translational space-time symmetry in the dynamical actions of all pre-inflationary "false vacuum" non-gravity quantum fields demands that all random incoherent virtual quanta inside the physical vacuum directly bend spacetime. This is unlike internal symmetry quantum electrodynamics where there is no direct "click" of a counter from a virtual photon. This distinction is garbled by many researchers in the field of "exotic propellantless propulsion," i.e. most of the STAIF presenters are unclear on this point.
Einstein's general rule for the bending of spacetime by an isotropic source, sans Casimir cavity-type boundary conditions, is
Guv ~ (G/c^2)(energy density of source)(1 + 3w)
w = pressure/(energy density)
Lorentz invariance + equivalence principle imply w = -1 for all zero point vacuum fluctuations of all non-gravity quantum fields.
(John Peacock, Cosmological Physics, p. 26, Cambridge)
bosons have positive zero point energy density
Therefore, boson ZPF has negative pressure and because of Einstein's isotropic coefficient of 3 universally repels as an anti- gravity field just like observed "dark energy."
fermions have negative zero point energy density, therefore fermion ZPF has positive pressure and again from the above factor of 3 it is an attractive anomalous source of gravity exactly like "dark matter." Although its locally w = -1, from a distance it is indistinguishable from w = 0 CDM in its clumping and gravity lensing and observed displacements of centers of CDM from visible atomic matter.
Note cold dark matter hypothetical on-shell particles have w ~ 0, but I say they do not exist in sufficient numbers to explain Omega (CDM) ~ 0.23 and the LHC will be mute on this just like Michelson- Morley experiment was mute on ether fringe shift of Earth's motion round the Sun.
Radiation has w = + 1/3
Therefore, with reference to the misleading remark below, negative energy density anti-gravitates only when w > - 1/3 which excludes isotropic zero point energy fluctuations. However, the loop hole is when cavity boundary conditions are important. For example, there may also be nonlocal order in 2D anyonic superconductors in which really we have 2D + 1 gravity rather than 3D + 1 gravity as in the above cosmological considerations. Hence the effective w for ZPF will shift for constrained geometries such as are to be expected to be found in alleged alien extra-terrestrial craft whose fuselages would obviously be nano-engineering quantum computing "smart AI" anyonic high Tc superconducting "macro-atoms" in active effective 2D + 1 moulded sheets only some tens of nanometers thick is my off- the-cuff guess.
Jack Sarfatti
"If we knew what
it was we were doing, it would not be called
research, would it?" -
Albert Einstein
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