  The quasiparticle excitation spectrum of an isolated vortex in a clean
layered d-wave superconductor is calculated, using both the Bogoliubov--de
Gennes and the quasiclassical Eilenberger equations. Analytical solutions are
obtained within the model of step-variation of the gap function, adjusting the
Caroli, de Gennes and Matricon approach for low-lying excitations in cuprates.
A large peak in the density of states in the "pancake" vortex core is found,
caused by the two-dimensional and strong coupling nature of high-temperature
superconductivity.
