Magnetic-Field Dependences of Thermodynamic Quantities in the Vortex   State of Type-II Superconductors
  We develop an alternative method to solve the Eilenberger equations numerically for the vortex-lattice states of type-II superconductors. Using it, we clarify the magnetic-field and impurity-concentration dependences of the magnetization, the entropy, the Pauli paramagnetism, and the mixing of higher Landau levels in the pair potential for two-dimensional $s$- and $d_{x^2-y^2}$-wave superconductors with the cylindrical Fermi surface. 
Koichi Watanabe, Takafumi Kita, Masao Arai