Relativistic approach to the tunneling-time problem

Abstract

We report a study of the effect of relativity on the tunneling time for the process of the tunneling ionization. Our results indicate that the relativistic effects make the tunneling time nonzero. A time interval of a few attoseconds is required for the electron to traverse the barrier. This finding agrees with the basic postulate of the special relativity that two events which are in causal relationship cannot occur simultaneously.