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We show that the recent experimental data of Toplicar and Finnemore on the superconducting proximity efiect in P&Cd thin films can be understood within the McMillan tunneling model by using our new transition temperature i'r,j formula and determining the parameters self-consistently. Agreement between the theoretical and the experimental values of T,, the gap, and the general shape and the height of the electronic density of state N,(E) curves is very good. In agreement with experiment, we find no low-energy peak in the density of states.Recently, Toplicar and Finnemore' (TF) published their results on the superconducting proximity effect in Pb-Cd thin films. They tried to understand their data in terms of the McMillan tunneling model' (MTM). However, the following discrepancies were found: (1) the theoretical electronic density of states curves for the ds = 330 A and ds = 670 A films (ds = thickness of Pb) were peaked much more than the experimental ones;(2) the theoretical value of the energy gap R for the ds = 670 A film was much lower than the experimental value; (3) for the ds = 670 '4 film, theory predicted a low-energy peak in the density of states which was absent in the data. The above authors could not find a plausible explanation for the discrepancies.In this paper we wish to point out that the discrepancies can be understood reasonably well by (1) using our new transition temperature (T,) formula, which is valid for the case of TzN # 0 (for Cd, TcN = 0.56 K) and (2) finding the parameters of the MTM self-consistently (whcih was not done by TF). In fact, point by point agreement between our theoretical and the experimental values of T, and R is excellent and, in agreement with *

The reduced specific heat jumps for the superconducting (S) side and the normal (N) side of a strongly coupled N-S composite have been calculated by using the generalized McMillan tunneling model of the superconducting proximity effect. Both cases AN = 0 and AN # 0 (where AN is the BCS interaction constant) have been stud&d. The results obtained by using the generalized model are significantly different from the ones given by the McMillan tunneling model.

The McMillan tunneling model of the superconducting proximity effect has been used to calculate the specific heat jumps on the S side and on the N side of a proximity composite. The case of the BCS interaction constant on the Nside, AN being identically zero and the case of AN r 0 have both been studied. The detailed dependence of the normalized specific heat jumps on the McMillan parameters Fs and FN and on the transition temperature of the composite has been computed. A reasonable agreement between our theoretical values and recent experimental data of Bevolo et al. is obtained.