Energy Harvesting

Understanding the motion at the nanoscale level is of ultimate importance. For example, Brownian motion has been observed and studied over one hundred years. The physical motion of nanoscale devices and structures are severely limited by Brownian noise. However, investigation of sub-nanoscale thermal (kT) motion of micron scale cantilevers leads us to believe that the cantilever is acting as a giant molecule with an energy kT. The amplitude of motion does not change significantly in vacuum, air, or liquid. Can we manipulate and control this kT motion such that we can beat the kT limit imposed by nature? The answer is a surprising yes! It is possible that this observation will lead to sensors and devices that beat the kT limit and revolutionize nanodevices and nanosensors. In addition, such understanding of the ever-present nanomechanical fluctuations and their control can play a significant role in understanding many biological phenomena.

The Brownian motion, or externally imposed motions, of cantilevers can be used for energy harvesting from the environment. For example, piezoelectric materials on a cantilever can convert the mechanical motion into electrical energy.