Artificial TE-mode surface waves at metal surfaces mimicking surface plasmons

Abstract

Manipulation of light in subwavelength scale can be realized with metallic nanostructures for TM-polarization components due to excitation of surface plasmons. TE-polarization components of light are usually excluded in subwavelength metal structures for mesoscopic optical interactions. Here we show that, by introducing very thin high index dielectric layers on structured metal surfaces, pseudo surface polarization currents can be induced near metal surfaces, which bring to excitation of artificial TE-mode surface waves at the composite meta-surfaces. This provides us a way to manipulate TE-polarized light in subwavelength scale. Typical properties of the artificial surface waves are further demonstrate for their excitation, propagation, optical transmission, and enhancement and resonances of the localized fields, mimicking those of surface plasmon waves.

Broadband transverse electric surface wave in silicene

“…On the other hand, the TE surface wave has the component of electric field transverse to the propagation direction while the magnetic field has a component parallel to the direction of propagation. The TE surface wave can be seen as a magnetic dipole wave on the surface of material due to the self-sustained surface current oscillation 7,8 .It is important to note that the radiation loss of magnetic dipole is much smaller than that of electric dipole 9 . Therefore, the TE surface wave can propagate longer than TM surface wave 10,11 , which makes the TE surface wave desirable for the transporting EM energy over long distance 7,11 .…”

“…The TE surface wave can be seen as a magnetic dipole wave on the surface of material due to the self-sustained surface current oscillation 7,8 .…”

“…On the other hand, the TE surface wave has the component of electric field transverse to the propagation direction while the magnetic field has a component parallel to the direction of propagation. The TE surface wave can be seen as a magnetic dipole wave on the surface of material due to the self-sustained surface current oscillation 7,8 .…”

“…Therefore, the TE surface wave can propagate longer than TM surface wave 10,11 , which makes the TE surface wave desirable for the transporting EM energy over long distance 7,11 . However, the TE surface wave cannot exist on the surface of an conventional bulk metal because condition for generating the TE mode is limited which means that the induced surface current is not available in the conventional bulk metal 1,2,7,12 .…”

“…In the case of TM surface wave, the component of magnetic field is transverse to the propagation direction, while the electric field has a component parallel to the propagation direction. The TM surface wave that also refers to a surface plasmon, can be seen as an electric dipole wave on the surface of material due to spatial perturbation of charge density 7,8 . On the other hand, the TE surface wave has the component of electric field transverse to the propagation direction while the magnetic field has a component parallel to the direction of propagation.…”