The Mudcat Café TM
Thread #59418 Message #1783048
Posted By: Amos
13-Jul-06 - 08:49 PM
Thread Name: BS: The Mother of all BS threads
Subject: RE: BS: The Mother of all BS threads
NOW the cat is really out of the Schrodingerian bag:
"The theory has been around for more than 40 years, but only now has it been confirmed through direct and unambiguous experimental results. Working at the Advanced Light Source (ALS) of the U.S. Department of Energy's Lawrence Berkeley National Laboratory, a team of researchers has observed the theoretical prediction of electron "spin-charge separation" in a one-dimensional solid. These results hold implications for future developments in several key areas of advanced technology, including high-temperature superconductors, nanowires and spintronics.
Just as the body and wheels of a car are thought to be intrinsic parts of a whole, incapable of separate and independent actions, i.e., the body goes right while the wheels go left, so, too, are electrical charge and spin intrinsic components of an electron. Except, according to theory, in one-dimensional solids, where the collective excitation of a system of electrons can lead to the emergence of two new particles called "spinons" and "holons." A spinon carries information about an electron's spin and a holon carries information about its charge, and they do so as separate and independent entities. Numerous experiments have tried to confirm the creation of spinons and holons, referred to as spin-charge separation, but it took the technological advantages offered at ALS Beamline 7.0.1, also known as the Electronic Structure Factory (ESF), to achieve success.
In a paper published in the June 2006 issue of the journal Nature Physics, researchers have reported the observation of distinct spinon and holon spectral signals in one-dimensional samples of copper oxide, SrCuO2, using the technique known as ARPES, for angle-resolved photoemission spectroscopy. The research was led by Changyoung Kim, at Yonsei University, in Seoul, Korea, ALS scientist Eli Rotenberg, and Zhi-Xun Shen of Stanford University, a leading authority on the use of ARPES technology. Co-authoring the Nature-Physics paper with them were Bum Joon Kim and Hoon Koh, plus S.J. Oh, H. Eisaki, N. Motoyama, S. Uchida, T. Tohyama, and S. Maekawa.
"There have been claims of observing the two peak spectral structures of spin-charge separation in the past, but they turned out to be wrong or have plenty of ambiguity. This was primarily because those results were obtained from complicated materials and were not theoretically backed up," said Kim, who has spent several years investigating the spin-charge separation phenomenon. "Our observations using ARPES are direct and the results are unambiguous because they were obtained from a simple material that left little room for misinterpretation. Also, our results are theoretically backed up."
Said Shen, "Our results confirming the idea of spin-charge separation are important because they reveal deep insights into the quantum system - and the beauty and subtleties associated with it. From this study we know more about how the collective behavior of a system of particles can be so fundamentally different from that of the constituent individuals."
The idea behind spin-charge separation is that electrons behave differently when their range of motion is restricted to a single dimension, as opposed to three or even two dimensions. When moving through one dimension, for example, the electrons are lined up head-to-tail, making the repulsive force between their negative electrical charges overridingly dominant. The restricted movement of electrons through one-dimensional material was expected to give rise to collective effects that would be strong enough to break the information flow of spin and charge from a single electron. "
Kinda makes it hadron the rest state of us, doesn't it?