Information carried by a surface-plasmon-polariton wave across a gap

Abstract

Faster communication between electronic devices inside a semiconductor chip may be enabled by optical interconnects based on surface-plasmon-polariton (SPP) waves, as their high localization overcomes the size mismatch between optical and electronic devices. Hence, we solved the Maxwell equations in the time domain to investigate the jump of a pulse-modulated carrier SPP wave across a semi-infinite gap on the metallic side of a planar metal/dielectric interface. The Drude model was used for the susceptibility of the metal and the air was taken as the dielectric material in our calculations. The Pearson correlation coefficient of the appropriate component of the Poynting vector at two points on either side of the gap was calculated. After an abrupt termination of the metal, reflection was very low and the signal continued to propagate in air as a precursor followed by a somewhat distorted version of the launched pulse. Information encoded as the existence of a pulse was found to be strongly and positively correlated with the transmitted signal. When the metal/air interface was restored after a gap of width equal to the carrier wavelength in free space, the signal received across the gap still comprised a precursor and a main pulse that were still strongly and positively correlated with the transmitted signal. Thus, information continued to propagate in the forward direction for a long distance after the gap, a promising result for SPP-wave-based optical interconnects.

Surface-plasmon-polariton wave propagation supported by anisotropic materials: Multiple modes and mixed exponential and linear localization characteristics

“…The constants C A1 and C A2 herein are determined by the boundary conditions at z = 0. Notice that the general solution (19) for the singular case contains a term that is linearly proportional to distance from the interface z, which is in stark contrast to the general solution (13) for the nonsingular case in Sec. 2.2.1.…”

“…arXiv:1907.07211v2 [physics.optics] 4 Sep 2019 readily achieved indirectly via coupling with a prism [2][3][4] or surface-relief grating [5], for examples. SPP waves are of major technological importance: they have been widely exploited for optical sensing [5-7] and microscopy [8,9], and applications for optical communications [10][11][12][13][14] and harvesting solar energy [15][16][17] are on the horizon.The theory underpinning SPP-wave propagation is firmly established in the case where the two partnering materials are isotropic [1]. The case where an isotropic plasmonic material is partnered with an anisotropic dielectric material has also been considered previously [18][19][20].…”

Information Transfer by Near-Infrared Surface-Plasmon-Polariton Waves on Silver/Silicon Interfaces

“…Furthermore, the amplitude of the electric field of the carrier SPP wave on the plane is modulated by the pulse functionwhere is the angular frequency of the carrier SPP wave and is the speed of light in free space. Thus, the electric field on the plane for all is specified as 16 where and are Cartesian unit vectors along the x and z axes, respectively. The free-space wavenumber of the carrier SPP wave in free space is denoted by ;is the complex wavenumber describing the propagation and attenuation of the carrier SPP wave along the silicon/silver interface 10–12 ; and the complex wavenumbersanddescribe field variation in the z direction.…”

“…The conditions , , and apply. Corresponding expressions for the magnetic field on the plane for all are available elsewhere 16 .…”

“…This is because a signal exists for a finite duration so that frequency-domain analysis of the Maxwell equations must be undertaken for a wide frequency range 14,15 . Direct time-domain analysis 16,17 using the finite-difference time-domain (FDTD) method 18,19 is straightforward for theoretical investigation of SPP-wave-based optical communication.…”