Local heat generated by a focused He ion beam.

A focused He beam with a beam diameter less than 1 nm is heating up the targeted surface for a He dose larger than 1 × 10 ions cm. The temperature can reach 1000 °C locally, resulting in surface decomposition or chemical reactions. This temperature was measured by fabricating gold nanodisks down to 20 nm in diameter and 10 nm in thickness on mica and sapphire surfaces.

The effect of magnesium ions on chromosome structure as observed by helium ion microscopy.

One of the few conclusions known about chromosome structure is that Mg2+ is required for the organization of chromosomes. Scanning electron microscopy is a powerful tool for studying chromosome morphology, but being nonconductive, chromosomes require metal/carbon coating that may conceal information about the detailed surface structure of the sample. Helium ion microscopy (HIM), which has recently been developed, does not require sample coating due to its charge compensation system.