Dysprosium-doped cadmium oxide as a gateway material for mid-infrared plasmonics

Abstract

The interest in plasmonic technologies surrounds many emergent optoelectronic applications, such as plasmon lasers, transistors, sensors and information storage. Although plasmonic materials for ultraviolet-visible and near-infrared wavelengths have been found, the mid-infrared range remains a challenge to address: few known systems can achieve subwavelength optical confinement with low loss in this range. With a combination of experiments and ab initio modelling, here we demonstrate an extreme peak of electron mobility in Dy-doped CdO that is achieved through accurate 'defect equilibrium engineering'. In so doing, we create a tunable plasmon host that satisfies the criteria for mid-infrared spectrum plasmonics, and overcomes the losses seen in conventional plasmonic materials. In particular, extrinsic doping pins the CdO Fermi level above the conduction band minimum and it increases the formation energy of native oxygen vacancies, thus reducing their populations by several orders of magnitude. The substitutional lattice strain induced by Dy doping is sufficiently small, allowing mobility values around 500 cm(2) V(-1) s(-1) for carrier densities above 10(20) cm(-3). Our work shows that CdO:Dy is a model system for intrinsic and extrinsic manipulation of defects affecting electrical, optical and thermal properties, that oxide conductors are ideal candidates for plasmonic devices and that the defect engineering approach for property optimization is generally applicable to other conducting metal oxides.

Large optical nonlinearity of nanoantennas coupled to an epsilon-near-zero material

“…Thus, ENZ material with lower intrinsic damping could increase the saturation threshold. The nonlinear response could be further enhanced by maximizing the overlap between the near-field of the antennas and the ITO layer, by choosing antennas (dielectric or metallic) with higher quality factors, and by choosing an ENZ material with lower intrinsic damping [18,36] .We note that when the ENZ medium is sufficiently thick, the antenna resonance gets locked to the zero permittivity wavelength of the ENZ material [37]. Nevertheless a metasurface that incorporates a thick ENZ material will also exhibit enhanced nonlinear response because a dynamic change in the substrate's refractive index necessarily modifies the resonance wavelength of the antenna.…”

“…Thus, ENZ material with lower intrinsic damping could increase the saturation threshold. The nonlinear response could be further enhanced by maximizing the overlap between the near-field of the antennas and the ITO layer, by choosing antennas (dielectric or metallic) with higher quality factors, and by choosing an ENZ material with lower intrinsic damping [18,36] .…”

Study of Composition and Morphology of Cadmium Oxide (CdO) Nanoparticles for Eliminating Cancer Cells

“…The action mechanism of Cadmium Oxide (CdO) nanoparticles is similar to other nanoparticles but its main activation is through destruction of the cell wall. This feature of Cadmium Oxide (CdO) nanoparticles makes them very useful for eliminating cancer cells [208][209][210][211][212][213].…”

Investigation of plasmon resonance tunneling through subwavelength hole arrays in highly doped conductive ZnO films

“…1,2 This phenomenon is also called "extraordinary optical transmission," which has been well-investigated over the past decade. [3][4][5] Recent works have studied mid-infrared (mid-IR) surface plasmon polaritons (SPPs) on dysprosiumdoped CaO 6 and arrayed structures fabricated in doped-Si, 7 InAs, 8 GaAs, 9,10 and InSb 11 as well as Cu-coated 12 and Ni 5,13 meshed structures with the doped-GaAs and Cu/Ni systems being specifically investigated.…”