I hope to know in most common cituations , what range the magnitude of the elastic scattering length and inelastic scattering length is in at low temperature for a strongle correlated system as well as a non-strong correlated sytem? and the possible references. Thank you very much!
I assume that you are talking about thermal neutron scattering from condensed matter. Coherent scattering lengths of neutron has been tabulated by Sears in International Tables of crystallography C (Dordecht, Amsterdam). Also you can get that easily from the NISTweb site
http://www.ncnr.nist.gov/resources/n-lengths/
The table also contain incoherent scattering lengths of the elements and their different isotopes. Neutron scattering lengths do not vary systematically as in the case of X-rays where scattering factor increases linearly with the atomic number. Coherent neutron scattering length varies irregularly from negative to positive values as the atomic number increases. Their values lie in the range (-10 to +20)x10^-13 cm . There exist no such straight forward inelastic scattering length or power. In case phonon scattering you calculate phonon structure factor and these structure factor is of course multiplied by the elastic scattering lengths only from the elements of your scatter. Read the book of Squire, Thermal neutron scattering, Cambridge.
Now if you come to magnetic materials then the elastic magnetic neutron scattering is governed by a few fundamental quantities (see Squire) and the magnetic moment of the atoms of your substance. For magnetic inelastic scattering you have to calculate magnon structure factor which involves geometry of the lattice and the magnetic moments of the atoms.
The neutron scattering from strongly correlated systems at low temperature is nothing different from other system so fas as scattering power is concerned. However to calculate phonon or magnon scattering cross section you must have a model Hamiltonian of the scattering system (magnetic) and there the physics of strongly correlated system comes.
You must read carefully the standard books on Thermal neutron scattering like that Squire, Lovsey, Marshall and Lovesy. But you can also consult "Magnetic neutron scattering" ed. T. Chatterji, Elsevier (2006).
Thank you very much！ Professor. Sorry, it's my fault to not state the question accurately. Actually, i want to know the scattering length of electrons related with the electron transport in a nomal system and a strong electron correlated system. The scattering mechanism in which would be the electron-electron scattering, the electron phonon scattering, electron defect scattering, etal.
OK. So you are talking about the transport and conductivity. I shall come back to it whenever I have some time.
Please read the paper M.I. Dykman et al., Phys. Rev. B 24, 16249 (1997) and also the papers of the References [6-18] of this paper. They have developed a techniques to calculate the scattering of correlated electrons and compared the results with those of non correlated limit. But these calculations are done in two-dimensional case. They have also calculated the magnetic field effect on transport.
- Badges
- Science topic
- Similar topics
- Physics
- Condensed Matter Physics