Cyclotron resonance for a spheroidal energy surface considers the energy surface where m_t is the transverse mass parameter and m1 is the longitudinal mass parameter. A surface on which ?(k) is constant will be a spheroid. Use the equation of motion (6), with v = h^?1 ?_k?, to show that wc = eB/ (m₁m_t)^1/2 c when the static magnetic field B lies in the xy plane. This result agrees with (34) when ? = ?/2, the result is in CGS; to obtain SI, omit the c.

/k + k k 2m) e(k) = i| 2m,