In the optical trap, there are three forces operating.
What the researchers have focused on is something that was pretty much known all along: optical traps are only conservative to a first approximation.
They specialize in holographic optical trapping, a technique for creating and moving many optical traps at once.
For quantitative scientific measurements, most optical traps are operated in such a way that the dielectric particle rarely moves far from the trap center.
In this way, an optical trap can be compared to a simple spring, which follows Hooke's law.
When implemented with a spatial light modulator, such holographic optical traps also can move objects in three dimensions.
A second type of optical trap is called an optical dipole trap.
If I recall, you have an optical trap under your countertop.
To reach the lowest possible temperature, further cooling is performed using evaporative cooling in a magnetic or optical trap.
They used another infrared laser to create an optical trap for the bead.