The recently discovered superconductivity in MgB2 has created the world
sensation. In spite of the relatively high superconducting transition
temperature Tc=39K, the superconductivity is understood in terms of rare two
gap superconductor with energy gaps attached to the sigma- and pi-band.
However, this simple model cannot describe the temperature dependent anisotropy
in H_c2 or the temperature dependence of the anisotropic magnetic penetration
depth. Here we propose a model with two anisotropic energy gaps with different
shapes. Indeed the present model describes a number of pecularities of MgB2
which have been revealed only recently through single crystal MgB2.Comment: 4 pages, 1 figure, to appear in Acta Physica Polonica B, proceedings
of the International Conference on Strongly Correlated Electron Systems,
SCES2002, Krakow, Polan