Effect of Zeeman splitting on magnetoresistivity of 2D hole gas in a   Ge_{1-x}Si_x/Ge/Ge_{1-x}Si_x quantum well
  For a two-dimensional (2D) hole system (confined within Ge layers of a multilayered p-Ge/Ge_{1-x}Si_x heterostructure) described by Luttinger Hamiltonian with the g-factor highly anisotropic for orientations of magnetic field perpendicular and parallel to the 2D plane (g_perp >> g_par), reported is an observation of low-temperature transition from metallic (dR/dT > 0) to insulator (dR/dT < 0) behavior of resistivity R(T) induced by a perpendicular magnetic field B. The revealed positive magnetoresistance scales as a function of B/T. We attribute this finding to a suppression of the triplet channel of electron-electron (hole-hole) interaction due to Zeeman splitting in the hole spectrum. 
Yu.G. Arapov, V.N. Neverov, G.I. Harus, N.G. Shelushinina, M.V.   Yakunin, O.A. Kuznetsov, A. de Visser, and L. Ponomarenko