The tunnelling current in reverse-biased Pb-p-Hg,-,Cd;Te (x = 0.2-0.3) Schottky barriers is investigated in a magnetic fieid H = 0-50 kOe parallel and perpendicular to the electric field E in the temperature range T = 20-250 K. The tunnelling current in magnetic fields of both orientations decreases by a factor of 10 and more. For H 11 E the magnitude of the effects as well as the dependence of the interband tunnelling current on magnetic fieid, reverse voltage (electric field), temperature and alloy composition is in good agreement with the theory. In contrast to the existing theory, for H I E orientation the magnetic-feid dependence is similar to t h e H 11 E case. No peculiarities are observed near the critical magnetic field H,, = cE/s (s is the Kane velocity). The experimental results for H I E may be explained qualitatively if we take into account a non-resonant scattering of light holes during tunnelling through the barrier. The scattering length estimated from the ratio of the effects in two orientations is proportional to H-'" and is of the order of the magnetic length. as would be exDected for quantum diffusion in crossed fields.

Quantum confinement is known to affect a nanosized superconductor through quantum‐size variations of the electronic density of states. Here, it is demonstrate that there is another quantum‐confinement mechanism overlooked in previous studies. In particular, it is found that the electron–electron attraction can be enhanced due to quantum‐confinement modifications of electronic wave functions. The superconducting correlations are strengthened by such quantum mechanical effect, which creates a subtle interplay with surface–substrate phonon modifications. The combined effect depends on nanofilm thickness and can be controlled by nanoarchitechture. The calculations are in a reasonable agreement with experiments performed on high‐quality aluminum films. These findings shed light on the long‐standing problem of the size dependence of the critical temperature in low‐dimensional superconductors.

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