Condensed matter physicists are known for creating miracles and they haven’t disappointed! They have just split the electron into two, creating a hitherto unobserved ‘orbiton’ in the process. While this has immediate consequences in theoretical condensed matter physics, like figuring out how high temperature superconductivity occurs (more later), the very idea of this is just too cool.
The ‘pieces’ of the electron
Condensed matter physicists have long identified that in a chain of atoms (called a ‘spin chain’), aligned in a particular direction, especially in the presence of a magnetic field, electrons can be thought of as particles being made up of three components. One component represents the charge(a ‘holon’), another the spin (a ‘spinon’) and a third one should store the orbital location information (an ‘orbiton’). Do note, however, that these three components exist independently only inside the material, not outside it. Outside the material, the electron is just the elementary particle – unbreakable into other particles – just like we know it to be.
Fifteen years ago, a team of scientists, led by C. Kim of Stanford University, split the electron into its holon and spinon components. The material they used was ‘one-dimensional’ Strontium Cuprate. Now, another team, led by J. van den Brink, have split the electron into a spinon and an orbiton, making it the first ever spectroscopic observation of a free orbiton. The material is another version of Strontium Cuprate.
Performing a miracle with a laser
The team fired a beam of X-ray photons into the one-dimensional material. The electrons in the outer orbitals were excited to a higher orbital. In this process, the electron can separate out into a spinon and an orbiton. And this is exactly what the scientists got.
When the electron got excited to a higher orbital, the laser light lost some energy. The scattered beam’s energy and momentum were plotted and compared with various computer simulations. The plot matched perfectly if one assumes that the electron has ‘split’ into an orbiton and a spinon. These two quasi-particles would be moving in opposite directions through the medium.
Van der Brink is more ambitious:
The next step will be to produce the holon, spinon and the orbiton at the same time
Problem in superconductivity
So what theoretical problem in superconductivity does it really solve?
The long standing problem in superconductivity (the phenomenon of flow of electric current through a material with zero resistance) has been the problem of high temperature superconductivity. No one know how some materials manage to superconduct at temperatures such as -196 degrees Celsius, which is much higher than the previously known -268 to -263 degree Celsius. No one knows what conducts the current through the material. There is a theory that orbitons might be the key.
To have the power to create your own materials and rediscover one of the oldest discoveries of ‘modern’ science is to be able to do modern day alchemy. It’s a miracle, indeed.
The paper appears here: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10974.html