Transmission times of wave packets tunneling through barriers

The transmission of wave packets through barriers by tunneling is studied i n detail by the method of quantum molecular dynamics. The distribution of t he arrival times of a tunneling packet in front of and behind a barrier and the momentum distribution function of the packet are calculated. The avera ge position and average momentum of the packet and their spread are investi gated. It is found that below the barrier a part of the packet is reflected , and a Gaussian barrier increases the average momentum of the transmitted packet and its spread in momentum space. (C) 1999 American Institute of Phy sics. [S1063-7761(99)02505-6].