Abstract: The present disclosure provides an optical waveguide design of a fiber modified with a thin layer of epsilon-near-zero (ENZ) material. The design results in an excitation of a highly confined waveguide mode in the fiber near the wavelength where permittivity of thin layer approaches zero. Due to the high field confinement within thin layer, the ENZ mode can be characterized by a peak in modal loss of the hybrid waveguide. Results show that such in-fiber excitation of ENZ mode is due to the coupling of the guided fundamental core mode to the thin-film ENZ mode. The phase matching wavelength, where the coupling takes place, varies depending on the refractive index of the constituents. These ENZ nanostructured optical fibers have many potential applications, for example, in ENZ nonlinear and magneto-optics, as in-fiber wavelength-dependent filters, and as subwavelength fluid channel for optical and bio-photonic sensing.

Abstract: The present disclosure provides an optical waveguide design of a fiber modified with a thin layer of epsilon-near-zero (ENZ) material. The design results in an excitation of a highly confined waveguide mode in the fiber near the wavelength where permittivity of thin layer approaches zero. Due to the high field confinement within thin layer, the ENZ mode can be characterized by a peak in modal loss of the hybrid waveguide. Results show that such in-fiber excitation of ENZ mode is due to the coupling of the guided fundamental core mode to the thin-film ENZ mode. The phase matching wavelength, where the coupling takes place, varies depending on the refractive index of the constituents. These ENZ nanostructured optical fibers have many potential applications, for example, in ENZ nonlinear and magneto-optics, as in-fiber wavelength-dependent filters, and as subwavelength fluid channel for optical and bio-photonic sensing.

Abstract: The present disclosure provides an optical waveguide design of a fiber modified with a thin layer of epsilon-near-zero (ENZ) material. The design results in an excitation of a highly confined waveguide mode in the fiber near the wavelength where permittivity of thin layer approaches zero. Due to the high field confinement within thin layer, the ENZ mode can be characterized by a peak in modal loss of the hybrid waveguide. Results show that such in-fiber excitation of ENZ mode is due to the coupling of the guided fundamental core mode to the thin-film ENZ mode. The phase matching wavelength, where the coupling takes place, varies depending on the refractive index of the constituents. These ENZ nanostructured optical fibers have many potential applications, for example, in ENZ nonlinear and magneto-optics, as in-fiber wavelength-dependent filters, and as subwavelength fluid channel for optical and bio-photonic sensing.

Abstract: The present disclosure provides a system and method for a tunable ENZ material that can vary the absorption of radiant energy. The tunable ENZ material can act as a broadband absorber advantageously using a stack of ultrathin conducting layers having an epsilon-near-zero (ENZ) regime of permittivity at different wavelengths. The conducting materials can include at least partially transparent conducting oxide or transition metal nitride layers with different electron concentrations and hence different ENZ frequencies for a broadband range of energy absorption. The layer(s) can be directly tuned to various frequencies to achieve high levels of absorption at deep subwavelength ENZ thicknesses. An applied electric bias can create electron accumulation/depletion regions in an ENZ semiconductor device and allows control of plasma frequency and hence high levels of absorption in the device. Further, for a stack of layers, the carrier concentration can be altered from layer to layer.

Abstract: The present disclosure provides a system and method for a tunable ENZ material that can vary the absorption of radiant energy. The tunable ENZ material can act as a broadband absorber advantageously using a stack of ultrathin conducting layers having an epsilon-near-zero (ENZ) regime of permittivity at different wavelengths. The conducting materials can include at least partially transparent conducting oxide or transition metal nitride layers with different electron concentrations and hence different ENZ frequencies for a broadband range of energy absorption. The layer(s) can be directly tuned to various frequencies to achieve high levels of absorption at deep subwavelength ENZ thicknesses. An applied electric bias can create electron accumulation/depletion regions in an ENZ semiconductor device and allows control of plasma frequency and hence high levels of absorption in the device. Further, for a stack of layers, the carrier concentration can be altered from layer to layer.