Figure 1

Explanation of resonantly enhanced tunneling. Tunneling of atoms out of a tilted lattice is resonantly enhanced when the energy difference between lattice wells matches the distance between the energy levels in the wells.Reuse & Permissions

Figure 2

Tunneling resonances in an accelerated optical lattice. (a) Tunneling resonances of the $n=1$ lowest energy level for $V_0=2.5E_{\mathrm{rec}}$. The arrows indicate the upper and lower limits for our precise measurement of ${\Gamma }_n$. Inset: Deviation from the Landau-Zener prediction. For clarity, in both graphs only one representative error bar is shown. (b) Positions of the $\Delta i=1$ resonance peaks as a function of the lattice depth. Only data points for which the resonance is clearly visible [e.g., not $\Delta i=1$ of (a)] are included. Inset: Positions of the peaks for $\Delta i=2$ and 3.Reuse & Permissions

Figure 3

Anticrossing scenario of the RET rates. (a) Theoretical plot of ${\Gamma }_{1,2}$ for $V_0=2.5E_{\mathrm{rec}}$ with experimental points for ${\Gamma }_1$. (b) Theoretical plot of ${\Gamma }_{1,2}$ for $V_0=10E_{\mathrm{rec}}$ with experimental points for ${\Gamma }_2$. For clarity, the vertical axes have been split and the ${\Gamma }_n$ plotted on a linear scale, and only one representative error bar is shown.Reuse & Permissions

Figure 4

Resonant tunneling in the nonlinear regime. (a) Resonance $\Delta i=3$ for $V_0=2.5E_{\mathrm{rec}}$ with $C=0.024$ (squares), $C=0.035$ (circles) and $C=0.057$ (triangles). The solid line is the theoretical prediction for $C=0$; the dashed lines are guides to the eye. (b) Dependence on $C$ of the tunneling rate at the position of the peak $F_0^{-1}=1.21$ (solid symbols) and of the trough $F_0^{-1}=1.03$ (open symbols). The dashed lines are fits to guide the eye. For clarity, in (a) and (b) only one typical error bar is shown.Reuse & Permissions