Exact vs . quasi - classical tunneling times for idealized potentials

We compare the exact tunneling time with the quasi-classical tunneling time for idealized potentials. We examine three one-dimensional cases where the potential is chosen to have a simple form. In each case, the exact tunneling time and the quasi-classical time differ significantly. In one case, the two differ in magnitude by a factor of about ten. In another case, the two differ not only quantitatively, but qualitatively as well. A discussion is given as to why the two times are significantly different, and suggestions for further inquiries are made. PACS Nos.: 03.65Xp, 03.65-w Résumé : Nous comparons les temps exact et semi-classique de la transition tunnel pour certains potentiels modèles. Nous examinons trois potentiels 1-D de forme simple. Dans tous les cas, le temps exact et le temps semi-classique diffèrent de façon significative. Dans un cas, ils diffèrent par un ordre de grandeur. Dans un autre cas, les deux diffèrent non seulement quantitativement, mais aussi qualitativement. Nous cherchons des causes possibles et suggérons des études additionnelles. [Traduit par la Rédaction]