Disintegrator gun
From Tardis Wiki, the free Doctor Who reference
The Disintegrator gun was a handheld weapon from an Alternate Earth in the 22nd century.
It employed an ultrasonic beam which effectively "disintegrated" the target. It was the weapon of choice of the human resistance opposing the Daleks and the Ogrons of that time in various forms.
They were apparently made of steel composites. (DW: Day of the Daleks)