Tunable circuit elements at optical frequencies using gyroelectric nanoparticles

This paper addresses the possibility of realizing fixed as well as variable electric circuit elements at infrared and visible frequencies using a gyroelectric nanosphere biased with a static magnetic field. With a proper choice of port designation, one might exercise field control over the impedance offered by the nanoparticle. It is shown that although the driving-point impedance looking into a pair of terminals chosen in some directions remains fixed, it can vary significantly in other directions with respect to the magnetic field biasing the particle. When combined with other isotropic nanocircuit elements, more complex tunable nanocircuits can be designed. This paves the way for adaptive nanosystems for smarter applications.