First a definition for this question, because there are many kinds of sci-fi out there and they sometimes liberally use cool sounding words without explaining them:
A disruptor is a kind of weapon that weakens, or “disrupts”, either material bonds (breaking a material into molecules), molecular bonds (breaking a molecule into atoms), or atomic bonds (breaking an atomic nucleus into protons, netrons, and free electrons. Almost like instantly turning into plasma).
Temperature can do these things, but the idea behind a disruptor, specifically, is that it happens through some kind of catalyst, rather than brute-forcing with insane amounts of heat.
Would such a weapon physically be possible (even if we don’t know how to make them just yet)?
How would a target realistically behave when hit by a disruptor?
Antimatter beam or Strangematter beam. When in doubt, just go increasingly quantum.