- #1
JanSpintronics
- 32
- 2
Hellooo
I have another questions about that fact that we have only a few solids that are ferromagnetic. In ferromagnetics i also read a few time ago it is important to consider 2 things about the reason why there is no magnetizaion. And i don't really understand both reasons, so i hope you can help me. So the both things are:
1. "The hybridization breaks spherical spherical symmetry for the environment of each atom, which tends to quench any orbital component of the magnetic moment."
So i don't see really why the case of no spherical movement of an electron will give less orbital magnetic moment. The magnetic moment of the electron is defined by its motion around a core and this motion will be still a motion around the core.
2. "Bandstructure also inhibits spin polarization. If one starts with a system of unpolarized electrons and imagines flipping spins to create alignment, then there is a kinetic-energy cost associated with moving electrons from lower-energy filled band states to higher-energy unoccupied band states. As a result, most solids are not ferromagnetic."
So i read that 2. sentence a thousand times but i really don't understand it...or what the author meant...
So far i know the consider a band with an unpolarized spin and than he imagines spin flipping of some electron in this band (correct?). Then he says its cost kinetic energy to move an electron from the lower band to the higher bbut what's the connection to the spin flipping and why does it cost kinetic energy besides the potentiell energy?
I have another questions about that fact that we have only a few solids that are ferromagnetic. In ferromagnetics i also read a few time ago it is important to consider 2 things about the reason why there is no magnetizaion. And i don't really understand both reasons, so i hope you can help me. So the both things are:
1. "The hybridization breaks spherical spherical symmetry for the environment of each atom, which tends to quench any orbital component of the magnetic moment."
So i don't see really why the case of no spherical movement of an electron will give less orbital magnetic moment. The magnetic moment of the electron is defined by its motion around a core and this motion will be still a motion around the core.
2. "Bandstructure also inhibits spin polarization. If one starts with a system of unpolarized electrons and imagines flipping spins to create alignment, then there is a kinetic-energy cost associated with moving electrons from lower-energy filled band states to higher-energy unoccupied band states. As a result, most solids are not ferromagnetic."
So i read that 2. sentence a thousand times but i really don't understand it...or what the author meant...
So far i know the consider a band with an unpolarized spin and than he imagines spin flipping of some electron in this band (correct?). Then he says its cost kinetic energy to move an electron from the lower band to the higher bbut what's the connection to the spin flipping and why does it cost kinetic energy besides the potentiell energy?