Actively tunable polar-dielectric optical devices

摘要

Optical devices that include one or more structures fabricated from polar-dielectric materials that exhibit surface phonon polaritons (SPhPs), where the SPhPs alter the optical properties of the structure. The optical properties lent to these structures by the SPhPs are altered by introducing charge carriers directly into the structures. The carriers can be introduced into these structures, and the carrier concentration thereby controlled, through optical pumping or the application of an appropriate electrical bias.

主权项

1. An actively tunable optical sensor, comprising:
a plurality of nanoantennas fabricated from a first polar-dielectric material configured to exhibit surface polar phonon polaritons (SPhPs) when the material is illuminated by an infrared optical probe beam having at least one wavelength within a Reststrahlen band of the polar-dielectric material, the nanoantennas having a resonant wavelength λres, a value of λres being affected by a presence of the SPhPs in the nanoantennas and being further affected by a concentration of charge carriers in the first polar-dielectric material; a probe beam source configured to provide the infrared optical probe beam to the plurality of nanoantennas; and a source of charge carriers controllably coupled to at least some of the nanoantennas; wherein the value of the resonant wavelength λres of the nanoantennas is actively tuned to coincide with an absorption wavelength characteristic of a specified analyte object by controllably injecting charge carriers from the source of charge carriers directly into at least some of the nanoantennas; and wherein the tuning of the resonant wavelength λresmodulates the probe beam to produce a desired output beam configured to indicate a presence of the specified analyte object by the sensor through absorption of the infrared probe beam within the Reststrahlen band of the polar-dielectric material.