ABSTRACT A sensor for measuring the amplitude and phase response of electromagnetic fields employing an optical sensing head is presented. The optical detection process enables field measurements undistorted by disturbances from metals due to wires and electronic circuitry. Up‐mixing of the signal to the optical domain by means of plasmonic antenna modulators enables measurements with optical tools, removing the need for high‐frequency electronics. Theory shows that sensitive field measurements only limited by thermal noise, can be achieved. Finally, the robustness of the suggested scheme is assessed in an experiment.
Baumann et al. (Wed,) studied this question.