PHYSICS · Multi-part · Fermi University Physics · Condensed Matter, Materials & Soft Matter · Electronic transport in solids · Electronic transport in solids
Solid State Physics, Ch The Boltzmann equation and electrical transport
Problem
A bar of gold containing a dilute, uniformly distributed concentration of zinc impurities (zinc has one more valence electron than gold, ΔZ=1) carries a steady electric current, driven by a uniform, time-independent electric field, at a single uniform temperature throughout the sample.
((a)) Write the semiclassical Boltzmann equation for the electron distribution function g(r,k,t), naming the physical process each term represents.
((b)) State which terms vanish for the steady, spatially uniform situation described, and write down the reduced equation that remains.
((c)) Identify, in one sentence, the physical scattering process represented by the collision term that survives, and name the length scale over which the mobile electrons screen a zinc ion's excess charge in this host.