RESUMO
Tamm plasmon polaritons (TPPs) have emerged as a promising platform for photodetector applications due to their strong light-matter interaction and potential for efficient light absorption. In this work, a design for a broadband photodetector (PD) based on the optical Tamm plasmon (OTS) state generated in a periodic metal-semiconductor-distributed Bragg reflector (DBR) geometry is proposed. The transfer matrix method (TMM) was used to study the propagation of electromagnetic waves through the proposed structure. By exciting the structure with incident light and analyzing the electric field profile within the multilayer structure at the resonant wavelength, we observe a distinctive electric field distribution that indicates the presence of Tamm plasmon modes. A comparative study was conducted to investigate the optical properties of a photodetector in the near-infrared (NIR) range by varying parameters such as thickness. By optimizing the thickness, we successfully achieved a broadband photoresponse in the photodetector, with a maximum responsivity of 21.8 mA/W at a wavelength of 1354 nm, which falls within the photonic bandgap region. FWHM was found to be 590 nm for the responsivity spectrum. The geometry also presents maximum absorption with FWHM calculated to be about 871.5 nm. The proposed geometry offers a broadband photoresponse, which is advantageous for the advancement of Tamm-based detector technologies. The ability to detect light over a wide operation range makes this mechanism highly beneficial for various applications.
RESUMO
Hybrid perovskites, as emerging multifunctional semiconductors, have demonstrated dual electronic/ionic conduction properties. We report a metal/ion interaction induced p-i-n junction across slightly n-type doped MAPbI3 single crystals with Au/MAPbI3/Ag configuration based on interface dependent Seebeck effect, Hall effect and time-of-flight secondary ion mass spectrometry analysis. The organic cations (MA+) interact with Au atoms, forming positively charged coordination complexes at Au/MAPbI3 interface, whereas iodine anions (I-) can react with Ag contacts, leading to interfacial ionic polarization. Such metal/ion interactions establish a p-doped region near the Au/MAPbI3 interface due to the formation of MA+ vacancies, and an n-doped region near the Ag/MAPbI3 interface due to formation of I- vacancies, consequently forming a p-i-n junction across the crystal in Au/MAPbI3/Ag configuration. Therefore, the metal/ion interaction plays a role in determining the surface electronic structure and semiconducting properties of hybrid perovskites.
RESUMO
A room temperature amorphous ferromagnetic oxide semiconductor can substantially reduce the cost and complexity associated with utilizing crystalline materials for spintronic devices. We report a new material (Fe0.66Dy0.24Tb0.1)3O7-x (FDTO), which shows semiconducting behavior with reasonable electrical conductivity (~500 mOhm-cm), an optical band-gap (2.4 eV), and a large enough magnetic moment (~200 emu/cc), all of which can be tuned by varying the oxygen content during deposition. Magnetoelectric devices were made by integrating ultrathin FDTO with multiferroic BiFeO3. A strong enhancement in the magnetic coercive field of FDTO grown on BiFeO3 validated a large exchange coupling between them. Additionally, FDTO served as an excellent top electrode for ferroelectric switching in BiFeO3 with no sign of degradation after ~1010 switching cycles. RT magneto-electric coupling was demonstrated by modulating the resistance states of spin-valve structures using electric fields.
RESUMO
The spin on a ferromagnetic Co surface can interact with the asymmetric orbital on an organometal halide perovskite surface, leading to an anisotropic magnetodielectric effect. This study presents an opportunity to integrate ferromagnetic and semiconducting properties through the Rasbha effect for achieving spin-dependent electronic functionalities based on thin-film design.