Periodic modulations of optical tweezers near solid-state membranes.

Optical tweezers operated near solid-state membranes show unexplained periodic modulations in the optical trap position. An experimental study of the oscillations is presented, as well as optical simulations based on the finite-difference time-domain method, providing insight into the underlying interference phenomenon. This work provides a complete description as well as a solution to the enduring problem of modulations in optical traps near solid-state membranes.