2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/99414An effective random matrix theory description is developed for the universal gap fluctuations and the ensemble averaged density of states of chaotic Andreev billiards for finite Ehrenfest time. It yields a very good agreement with the numerical calculation for Sinai-Andreev billiards. A systematic linear decrease of the mean field gap with increasing Ehrenfest time $τ_E$ is observed but its derivative with respect to $τ_E$ is in between two competing theoretical predictions and close to that of the recent numerical calculations for Andreev map. The exponential tail of the density of states is interpreted semi-classically.4 pages, 4 figuresMesoscale and Nanoscale PhysicsSuperconductivitytext