1 research outputs found
Optical Nanoantenna Input Impedance
Optical nanoantennas
have been studied as a means to manipulate
nanoscale fields, local field enhancements, radiative rates, and emissive
directional control. However, a fundamental function of antennas,
the transfer of power between a coupled load and far-field radiation,
has seen limited development in optical antennas owing largely to
the inherent challenges of extracting impedance parameters from fabricated
designs. As the transitional element between radiating fields and
loads, the impedance is the requisite information for describing,
and designing optimally, both emissive (transmitting) and absorptive
(receiving) nanoantennas. Here we present the first measurement of
an optical nanoantenna input impedance, demonstrating impedance multiplication
in folded dipoles at infrared frequencies. This quantification of
optical antenna impedance provides the long sought enabling step for
a systematic approach to improve collection efficiencies and control
of the overall antenna response