Surface magneto plasmons and their applications in the infrared frequencies

Abstract

Due to their promising properties, surface magneto plasmons have attracted great interests in the field of plasmonics recently. Apart from flexible modulation of the plasmonic properties by an external magnetic field, surface magneto plasmons also promise nonreciprocal effect and multi-bands of propagation, which can be applied into the design of integrated plasmonic devices for biosensing and telecommunication applications. In the visible frequencies, because it demands extremely strong magnetic fields for the manipulation of metallic plasmonic materials, nano-devices consisting of metals and magnetic materials based on surface magneto plasmon are difficult to be realized due to the challenges in device fabrication and high losses. In the infrared frequencies, highly-doped semiconductors can replace metals, owning to the lower incident wave frequencies and lower plasma frequencies. The required magnetic field is also low, which makes the tunable devices based on surface magneto plasmons more practically to be realized. Furthermore, a promising 2D material-graphene shows great potential in infrared magnetic plasmonics. In this paper, we review the magneto plasmonics in the infrared frequencies with a focus on device designs and applications. We investigate surface magneto plasmons propagating in different structures, including plane surface structures and slot waveguides. Based on the fundamental investigation and theoretical studies, we illustrate various magneto plasmonic micro/ nano devices in the infrared, such as tunable waveguides, filters, and beam-splitters. Novel plasmonic devices such as one-way waveguides and broad-band waveguides are also introduced.

Thermal spin photonics in the near-field of nonreciprocal media

“…We further note that the practical example considered here can also lead to unidirectional energy transport because of nonreciprocity [42,47,48]. However, unidirectional transport is not a cause of PTPS and PPHC and this is explained in the following.…”

“…We consider doped Indium Antimonide (InSb) slab which has been most widely studied in the context of coupled magneto-plasmon surface polaritons [41,42] and whose material permittivity dispersion has been wellcharacterized experimentally [43][44][45][46]. For the sake of completeness of our study, we extend the known permittivity model in [44][45][46] to the case of an arbitrarily oriented magnetic field in our geometry and obtain the semi-analytic form of permittivity given by e e w w w where m e =9.109 4×10 −31 kg is electron mass.…”

Unidirectional reflectionless light propagation at exceptional points

“…Tuning the geometry rather than the refractive index can reduce the difficulty in the experimental realization of such structures. Among different plasmonic waveguide structures, MDM plasmonic waveguides are of particular interest [108][109][110][111][112][113][114][115][116], because they support modes with deep subwavelength scale over a very wide range of frequencies extending from DC to visible [117] and are relatively easy to fabricate [118,119]. The waveguide widths w, w 1 , and w 2 are set to be 50, 20, and 100 nm, respectively ( Figure 9A).…”

Integrated nanoplasmonic waveguides for magnetic, nonlinear, and strong-field devices

“…These material systems can produce appreciable magneto-optic effects under stimulus from weak magnetic fields, which can be practically generated for integrated applications. For completeness, we note here that doped semiconductors are utilized in the infrared and terahertz regimes; this technology has been extensively reviewed in the past [69,70] and is not the focus of the present work.…”