Speaker
Description
The influence of relativistic effects on tunnel ionisation of electronic systems was described in detail by theory. For hydrogen-like ions of atomic charge $Z$ and laser radiation intensity $I$ these effects become significant for $Z > 45 (I/I_0)^{0.1}$, with $I_0=10^{22}\,$W/cm$^2$. This motivates the use of highly-charged ions to investigate ionisation. Suitable candidates are hydrogen-like ions, such as O$^{7+}$ or Ne$^{9+}$, as the average electric field over the 1s orbital is comparable to the electric fields of current laser systems.
To prepare a target of highly charged ions we have devised the HILITE (High-Intensity Laser Ion-Trap Experiment). The setup can store several thousand ions in a controlled ion cloud using a Penning trap. The whole setup is transportable to be used at high-power laser facilities. It includes an Electron-beam ion trap (EBIT) which can create a wide range of highly-charged ions. The produced ion bunches with a kinetic energy of about $2\,$keV/q are deflected by a 90° electrostatic detector. It includes two sikler lenses to compensate for the stray magnetic field of the 6$\,$T magnet. The beamline also contains three non-destructive image charge detectors to track the ions bunches. The ions are decelerated using a two stage deceleration system and captured dynamically.
To manipulate and detect the stored ion cloud we use common procedures, such as resistive cooling, SWIFT, FT-ICR and the rotating wall technique.
We present the setup and characterisation measurements with stored Ne$^{7+}$ ions and we will give an outlook on the planned laser-ion experiments at the Jena high-power laser system JETI200.
