Electrical modulation of degenerate semiconductor plasmonic interfaces

Abstract

We demonstrate electrical modulation of plasmonic interfaces in semiconductor p-n++ junctions fabricated from both III–V and Si materials. Junction diodes are grown/fabricated, consisting of degenerately doped n-type material and heavily doped p-type material, where the n++ semiconductor acts as a plasmonic material capable of supporting infrared propagating surface plasmon polaritons. Devices were characterized electrically and optically, and we achieved tuning of the reflectivity under applied bias with amplitude reaching 1.5% in mid-IR wavelengths. We developed a model of electrical carrier injection at the degenerately doped interface, which we used to model the bias-dependent optical properties of the system. A strong agreement between our model and experimental results is demonstrated. The presented devices offer the opportunity for electrical modulation of propagating plasmonic modes in an all-semiconductor system.

Tunable Surface Plasmon Polaritons with Monolithic Schottky Diodes

“…In this case, the ideal modulation range of the transmission and absorption is 67% and 32%, respectively, and the corresponding differential transmission is as high as 573. Due to the large distance between the ohmic and Schottky contacts, the applied bias here is higher than several reported works. , However, the applied bias is dominantly dropped over the long IGZO channel, and the power dissipation is distributed over a wide range. Several devices have been tested successfully without any breakdown in the aforementioned voltage range.…”

“…Apart from passive SPPs, active SPP devices with electrically tunable properties enable applications in real-time controllable subwavelength circuits, such as switches, attenuators, and phase and frequency shifters, etc. , At optical frequencies, liquid plasmonic materials, ferroelectric materials, semiconductors, and P–N diodes have been studied to actively manipulate SPPs. − However, their modulation depth is typically less than 20%. To achieve tunable SPPs at microwave frequencies, commercially purchased chips, such as varactor diodes, have been soldered on SPP devices. − However, these soldered chips were not monolithically fabricated with the SPP structures.…”

Simultaneous Control of Spectral And Directional Emissivity with Gradient Epsilon‐Near‐Zero InAs Photonic Structures

“…[ 35‐43 ] Due to this capability, prior studies have used doped semiconductor‐based platforms to demonstrate Tamm plasmon polariton emitters [ 44,45 ] and dynamic thermal emission control. [ 46‐48 ] Broadband omnidirectional emissivity was also demonstrated using resonances supported in semiconductor nanostructures. [ 13,14,49 ] Doped semiconductors have also been used to demonstrate Berreman mode‐driven behavior, including directional emission, but only over a narrow bandwidth of operation.…”

Response times of a degenerately doped semiconductor based plasmonic modulator

“…In this work, we present a significant step towards realizing a complete semiconductorbased plasmonic switch referred to as a Surface Plasmon Polariton Diode (SPPD) [62][63][64][65]. Here, we build upon our past work [65], where we have demonstrated excitation and modulation of SPPs modes at the interface of the degenerately doped lattice-matched Indium Gallium Arsenide (In0.53Ga0.47As) PN ++ -junctions grown epitaxially on Indium Phosphide (InP) and proceed to the next important step by experimentally demonstrating the temporal response of the device.…”

“…These reflection features correspond to coupling into electromagnetic (EM) modes supported either at the PN ++interface or in the higher index P-layer of the device. To investigate these spectral features, we modified the already-developed COMSOL-based electro-optic model [62][63][64][65] to solve for the current device architecture and proceeded to numerically examine the fabricated SPPD. Essential parameters required to effectivity replicate the fabricated PN ++ -junction such as doping concentrations at thermal equilibrium, junction depth, doping dependent and electron and hole mobilities and scattering rates, are used from our previous work [65].…”