Figure 1

Chip design: a magnetic side guide is modulated by applying voltages to the set of six electrodes (dark gray in center plot). Equipotential surfaces ($E_{\mathrm{p}\mathrm{o}\mathrm{t}}=k_B\times 475\mu \mathrm{K}$) are shown for ${}^7\mathrm{L}\mathrm{i}$ atoms in the $|F=2,m_F=2⟩$ ground state for the side guide (top) and a string of six combined electromagnetic traps (center). A contour plot of the electric field strength at the plane parallel to the chip at the height of the minimum ($z=50\mu \mathrm{m}$) is also depicted (bottom). The parameters chosen for these numerical calculations were $I_{\mathrm{w}\mathrm{i}\mathrm{r}\mathrm{e}\mathrm{,}\mathrm{y}}=1\mathrm{A}$, $B_{\mathrm{b}\mathrm{i}\mathrm{a}\mathrm{s}\mathrm{,}\mathrm{x}}=40\mathrm{G}$, and $V_{\mathrm{e}\mathrm{l}\mathrm{e}\mathrm{c}}=+475\mathrm{V}$.Reuse & Permissions

Figure 2

Time series of fluorescence signals in experiments demonstrating the trapping of thermal ${}^7\mathrm{L}\mathrm{i}$ atoms in combined electromagnetic traps: (left) At $t=0$, a cloud of atoms is released from a magnetic Z trap into an open L-shaped guide where the guiding wire is broadened at the open end on the right-hand side, guiding the atoms towards the chip surface where they are lost. (right) If a voltage is applied to the electrodes along the guide, atoms remain in six individual trap sites. (top right) The actual chip design used in these experiments with the different current carrying and charged structures. The parameters used in this case were $I_{\mathrm{w}\mathrm{i}\mathrm{r}\mathrm{e}}=1.6\mathrm{A}$, $B_{\mathrm{b}\mathrm{i}\mathrm{a}\mathrm{s}}=44\mathrm{G}$, and $V_{\mathrm{e}\mathrm{l}\mathrm{e}\mathrm{c}}=+300\mathrm{V}$.Reuse & Permissions

Figure 3

(left) An atom cloud confined in a single combined electromagnetic trap ($I_{\mathrm{w}\mathrm{i}\mathrm{r}\mathrm{e}}=1.5\mathrm{A}$, $B_{\mathrm{b}\mathrm{i}\mathrm{a}\mathrm{s}}=30\mathrm{G}$, and $V_{\mathrm{e}\mathrm{l}\mathrm{e}\mathrm{c}}=280\mathrm{V}$) is smoothly transported along the magnetic side guide. (center) Longitudinal profile of the atom distribution as the cloud is transferred over a distance of $400\mu \mathrm{m}$ during 30 ms. The voltages on the different electrodes at the different phases of the transfer are depicted schematically. (right) The timing of the voltage ramps was chosen to allow a smooth transfer from one trapping site to another while maintaining a nearly constant trap depth of $50–60\mu \mathrm{K}\times k_B$.Reuse & Permissions

Figure 4

Dynamic splitting of an atom cloud. A single trap is gradually (within 15 ms) turned into a double well potential by ramping the voltage on one electrode down while two neighboring electrodes are slowly charged. (top) Fluorescence images of the atoms during different stages of the experiment. (center) The density profile clearly shows the gradual splitting of a single cloud into two. The insets schematically show the polarities and voltages (darker shading corresponds to higher voltage) during the different phases of the experiment. (bottom) The corresponding potentials along the axis of free motion in the magnetic guide.Reuse & Permissions