[11p-Z08-1~19] 10.1 新物質・新機能創成（作製・評価技術）

▲ [11p-Z08-7] Transverse Magneto-Optical Kerr Effect of Fe_xCu_x Superlattices for Surface Plasmon Resonance Application: First Principle Study

〇(D)Muhammad Arifin^1,2、Kohji Nakamura¹ (1.Graduate School of Engineering, Mie University, Japan、2.Department of Physics, Gadjah Mada University, Indonesia)

キーワード：transverse magneto-optical Kerr effect, first-principles calculations, superlattices

Recently, much interest in Surface Plasmon Resonance (SPR) application has been made in optical devices as biosensors in the fields of health diagnosis and food safety. [1, 2] For achieving high sensitivity, one alternative technique has been proposed by optimizing the plasmonic layer that excites the magneto plasmonic effect by employing the transverse magneto-optic Kerr effect (TMOKE), so-called magneto-optical Surface Plasmon Resonance (MOSPR). In the present work, the magnetic and magneto-optical properties of ferromagnetic/noble metal superlattices, Fe_x/Cu_x, where x is the number of atomic-layers, are studied from first-principles calculations. Calculations were carried out by using a full-potential linearized augmented plane wave (FLAPW) method with the generalized gradient approximation. [3] The diagonal and off-diagonal parts of absorptive optical conductivity tensor, Re(σ_xx) and ωIm(σ_yz), were estimated by linear response theory. As far as the magnetic properties are concerned, a significant increase of magnetic moment of Fe in the system is observed, it ranges between 2.65 and 2.66 µ_B, while Cu possess an induced magnetic moment, which is characterized by its small value. The optical spectrum Re(σ_yz) shows the first peak shift of the energy position to 1.7 eV, 2.4 eV and 1.9 eV for x =1, 2 and 3, respectively, compared to value of 2.7 eV for pure body-centered-cubic (bcc) Fe. Assumed the Kretschmann configuration with the 4 × 4 transfer matrix method [4], we have simulated the MOSPR system for blood serum (n = 1.346) as a sample. The resonance condition in the SPR spectra occurs at an incident angle of 75.5°. On the other hand, the MOSPR signal in the resonance condition increases proportionally to the number of x in Fe_xCu_x. The enhancement of the S-shaped resonance of the MOSPR signal is caused by a shift in resonance features observed in reflectance. [5]