Published in Physics World, 22 Jan 2010
Physicists in Germany claim to have trapped single ions using lasers for the first time – an achievement that could open the door to advanced simulations of quantum systems.
In the past, the trapping of atomic particles has followed a basic rule: use radio-frequency (RF) electromagnetic fields for ions, and optical lasers for neutral particles, such as atoms. This is because RF fields can only exert electric forces on charges; try to use them on neutral particles and there’s little effect. A laser, on the other hand, can draw the dipole moments of neutral particles towards the centre of its beam. But the resultant optical trap is relatively weak, and so ions – which are sensitive to stray electric fields – easily escape. […]
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