Zero or targeted heat input
With laser pulses of a few pico- and femtoseconds, materials can be efficiently processed, practically without thermal or mechanical influences. To do this, the laser pulse – and therefore the duration of the energy input – must be short enough in order to avoid temperature compensation between electrons and their associated atoms. The material evaporates abruptly. The heat does not get into the surrounding material, and thermal stress fractures are avoided. This is referred to as "cold processing". For metals and many other materials, the ideal pulse duration for this is between 1 and 10 picoseconds.
