Wannier-Stark states in finite superlattices.
Individual Wannier-Stark states are resolved in a current experiment over a wide electric-field range for a 5 and 4 period finite superlattice utilizing a hot-electron transistor. The observed field dependence of the tunneling transmission through the various states directly resembles the progressive localization of the wave functions. The basic transport through Wannier-Stark states in short-period superlattices is identified to be coherent. By tuning the Wannier-Stark state splitting with electric field into the optical phonon energy, the opening of new LO-phonon mediated transport paths is observed.
Kast
M
M
Institut für Festkörperelektronik, Technische Universität Wien, Floragasse 7, A 1040 Wien, Austria. michael.kast@tuwien.ac.at
Pacher
C
C
Strasser
G
G
Gornik
E
E
Werner
W S M
WS