PHY 1850 F

Homework #4

 

#1:     Kittel  11-1 & 11-8 (Quantum diamagnetism & paramagnetism)

#2:     Kittel  11-5 (Pauli spin susceptibility) 

#3:     Kittel  11-6 (Conduction-electron ferromagnetism)

#4:     Kittel  12.1  (Magnon dispersion relation)  

#5:
     Kittel  12.2  (Heat capacity of magnons)

#6:     Kittel  12.3 & 12.6 (Neel temperature & Saturation magnetization)  

#7:     Kittel  12.8 (Giant magnetoresistance)

Extra Credit:   d-wave van Hove singularity (A numerical problem)


          Noting that dI/dV ~ , and using the expression for quasiparticle tunneling current

            from many-body formalism (see supplementary note).

 
               

           Compute and plot the quasiparticle density-of-states  for a superconductor

           with the two-dimensional tight-binding dispersion: ;  
           where
t=250meV and
=500meV, and the d-wave gap-function:
                         ;   where =25meV.

             Note: in the normal state (= 0), there exist a singularity in  at the Fermi level (E=0)