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Homework Help: Solid state physics-effective mass problem.

  1. Jan 29, 2012 #1
    1. The problem statement, all variables and given/known data

    Tha band structure of a simple cubic lattice is given by,

    [itex]E = E_{0}-A(\cos k_{x}a+\cos k_{y}a+\cos k_{z}a)[/itex]

    where a is the lattice constant and A is a positive constant.

    Find the effective mass for the electron at the values of k corresponding to the top and bottom of the band.

    2. Relevant equations

    [itex]m^{\ast }=\frac{\hbar ^{2}}{\left( \frac{d^{2}E}{dk^{2}}\right) }[/itex]

    3. The attempt at a solution

    The components kx,ky,kz and the condition 'top and bottom of the band' are confusing me.
    Is these top and bottom correspond to brollouin zone edges?
    How can i put these components of k in above equation?

  2. jcsd
  3. Jan 30, 2012 #2
    Hi friends, need help here.:wink:
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