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Updated: Aug 29, 2026

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Asymmetric Landau-Zener tunneling in a periodic potential
M Jona-Lasinio1, O Morsch, M Cristiani
1INFM, Dipartimento di Fisica E. Fermi, Università di Pisa, Via Buonarroti 2, I-56127 Pisa, Italy.
Abstract:
Using a simple model for nonlinear Landau-Zener tunneling between two energy bands of a Bose-Einstein condensate in a periodic potential, we find that the tunneling rates for the two directions of tunneling are not the same. Tunneling from the ground state to the excited state is enhanced by the nonlinearity, whereas in the opposite direction it is suppressed. These findings are confirmed by numerical simulations of the condensate dynamics. Measuring the tunneling rates for a condensate of rubidium atoms in an optical lattice, we have found experimental evidence for this asymmetry.
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