Size quantization effect in graphite based proximity systems

We discuss size-quantization (SQ) effects in a proximity system made of a graphite thin film deposited onto a superconductor. We show that SQ leads to oscillations of the superconducting critical temperature $T_c$ as a function of the thickness of the graphite layer. This oscillation is due to the peculiar behavior of the density of state in size-quantized systems. The calculated period is directly related to major parameters of the semimetal and thus to the normal state properties of the bilayer. Recent experiments made on graphite/superconductor bilayers are discussed in the framework of the theory.