Real laser sound
There isn't actually a real world laser sound that exsists. This is because its a different spectrum than molecules in the air or other medium that sound energy is transmitted. This is why the sun doesn't make a noise when it comes and goes behind clouds.
But lasers need a sound!
Ok so we are in a world where we all know of cool laser sounds and know it's not a real laser if it is silent. Unless you listen really hard to those mission impossible beams. For a laser sound like a bank heist you need a low tone like a florescent light or hum to show the laser is being produced and using electricity. This has to be experimentation for how evil or soft you want the laser to sound.
To make your sounds more dynamic try to use as much of the frequency range as you can. Or instance in a bank heist the music might play low in the spectrum and your lasers will cut through in a mid-high range and breathing lies in the middle.
But mine is a laser gun sound!
Ok well one of the best ways to get a base layer for a laser gun sound is a good pulse sound like the guns in Wall-E. This was created by Ben Burtt who has films like star wars to draw his knowledge from. He used a metal slinky hanging off a ladder so it's suspended from the floor. Then positioned the microphone at the very bottom, facing up the center of the slinky. Taking a metal bar he struck the slinky and then the sound travels down the slinky to the microphone in a pulse.
Give it a try yourself!