Some day, you may have a microscope on your smartphone camera that’s as powerful as a scanning electron microscope. If you do, it will likely be thanks to research presently being conducted by Durdu Guney, an assistant professor of electrical and computer engineering at Michigan Technological University. He is working on creating a metamaterial-based “superlens” – a long sought-after optically-perfect lens, that could use visible light to image objects as small as 100 nanometers across.
Currently, optical lenses are limited by natural light’s diffraction limit, and are thus typically unable to see objects smaller than about 200 nanometers. While scanning electron microscopes are able to image much smaller details, they are costly, non-portable, and thus not available for most people to use.
For his superlens, Guney is looking to plasmons – particles of oscillating plasma. In his model, plasmons located near the surface of thin metal films are combined with special nanostructures. When they’re subjected to an electromagnetic field, they take in light waves reflected from an object, and negatively refract them. In so doing, the diffraction limit is overcome. According to the model, such an arrangement should allow for the viewing of items less than one one-thousandth the width of a human hair, using natural light.
According to Guney, such lenses would be inexpensive to create, which is why they could conceivably end up in consumer products. He states that they could also be used in lithography for making low-cost tiny electronic items, and for replacing expensive UV lasers by intensely focusing the beam of ordinary visible-light red lasers.