Hybrid structures of magnetic semiconductors and plasmonic crystals: a novel concept for magneto-optical devices [Invited]

Abstract

We propose here to combine magnetic semiconductors and plasmonic crystals to obtain a new class of devices, in which magneto-optical effects are dramatically enhanced. So far we have studied the two building blocks separately, and we demonstrate here features of these systems that make them appealing for combination. Namely, for magnetic semiconductors we demonstrate efficient tools for manipulating their magnetization. In particular, we show that in paramagnetic (Ga,Mn)As the magnetic ions can be oriented optically. For ferromagnetic (Ga,Mn)As an ultrafast strain pulse moves the magnetization out of its equilibrium position, inducing a subsequent precessional motion about the equilibrium orientation. For plasmonic crystals, on the other hand, we show that the magnetooptical effects are dramatically enhanced in both reflection and transmission. From combining the two systems, we expect to be able to obtain magneto-optical materials that can be controlled efficiently through manipulation of the magnetization of the magnetic semiconductor onto which the plasmonic crystal is deposited.

Coupled mode enhanced giant magnetoplasmonics transverse Kerr effect

“…(7) and the second term represents the shift originating from the magneto-optical effect. Our model of the spectral shift of SPP by TMOKE is equivalent with previously used model of SPP shift [13,20]. Figure 8 shows analysis of the shift of SPP calculated (at the photon energy 1 eV) from exact model Eq.…”

“…The latter hybridization of these resonances is strongly dependent on the precise geometrical parameters of the grating and can greatly influence the efficiency of the EOT effects at play [17,18]. In EOT gratings on MO substrates [19][20][21], the role of the FP cavity modes has commonly been neglected in view of the limited interaction that they present with the MO material. As a result the influence on the magnetoplasmonic properties of geometrical dispersion and the resulting resonance hybridization has not been investigated.…”

Tuning of the transverse magneto-optical Kerr effect in magneto-plasmonic crystals

“…The combination of plasmonics and magneto-optics looks mutually beneficial. On the one hand, the magnetic field is an efficient tool to control SPPs [12,13], and on the other hand SPPs can be utilized to enhance magnetooptical effects [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. Early papers on the interplay between SPPs and magneto-optics addressed SPPs propagating along the smooth surface of a ferromagnetic film [31,32] or along a smooth semiconductor surface in an external transverse magnetic field [33,34].…”

Terahertz dynamics of lattice vibrations in Au/CdTe plasmonic crystals: Photoinduced segregation of Te and enhancement of optical response

“…Based on these principles, surface plasmon resonant sensors for the detection of chemical and biological species are developed [3]. In addition, one can use an external stimulus such as optical excitation [4][5][6][7][8], acoustic waves [9][10][11][12] and external magnetic fields [13][14][15][16] in order to influence the dielectric function of metal and/or dielectric and subsequently to control the SPP propagation constant. Therefore, SPPs are well suited for applications in optoelectronic devices where high sensitivities * lars.kreilkamp@tu-dortmund.de and efficient optical excitation at the nanoscale are essential [8].…”