Photovoltaic enhancement due to surface-plasmon assisted visible-light absorption at the inartificial surface of lead zirconate-titanate film

Mid-Infrared Response from Cr/n-Si Schottky Junction with an Ultra-Thin Cr Metal

Infrared detection technology has been widely applied in many areas. Unlike internal photoemission and the photoelectric mechanism, which are limited by the interface barrier height and material bandgap, the research of the hot carrier effect from nanometer thickness of metal could surpass the capability of silicon-based Schottky devices to detect mid-infrared and even far-infrared. In this work, we investigate the effects of physical characteristics of Cr nanometal surfaces and metal/silicon interfaces on hot carrier optical detection. Based on the results of scanning electron microscopy, atomic force microscopy, and X-ray diffraction analysis, the hot carrier effect and the variation of optical response intensity are found to depend highly on the physical properties of metal surfaces, such as surface coverage, metal thickness, and internal stress. Since the contact layer formed by Cr and Si is the main role of infrared light detection in the experiment, the higher the metal coverage, the higher the optical response. Additionally, a thicker metal surface makes the hot carriers take a longer time to convert into current signals after generation, leading to signal degradation due to the short lifetime of the hot carriers. Furthermore, the film with the best hot carrier effect induced in the Cr/Si structure is able to detect an infrared signal up to 4.2 μm. Additionally, it has a 229 times improvement in the signal-to-noise ratio (SNR) for a single band compared with ones with less favorable conditions.

Controlled high-quality interface of a Ti2.5O3(0 1 0)/GaAs(0 0 1) heterostructure enabled by minimized lattice mismatch and suppressed ion diffusion

Metal oxide/semiconductor heterostructures exhibit great potential for high-performance electronic device applications, but the interfacial defects resulting from lattice mismatch pose significant challenges to improving the performance of these devices. In this study, we reported a construction of a single crystal Ti_2.5O₃/GaAs heterostructure with minimum lattice mismatch between titanium sub-oxides and GaAs substrate. Low lattice mismatch values of 0.3% or 0.6% can be achieved along different orientations. Further experimental analyses demonstrate that high crystalline Ti_2.5O₃ (0 1 0) film can be grown layer by layer on GaAs (0 0 1) substrate with highly compatible interface. The defect-free interface significantly suppresses the diffusion of As and Ga ions, which impedes the formation of arsenic oxide and gallium oxide at the interface. Due to the high-quality Ti_2.5O₃ layer, the integrated BaTiO₃(250 nm)/SrTiO₃/Ti_2.5O₃(5 nm)/GaAs heterostructure exhibits an enhanced hysteresis loop with a remnant polarization of 9.85 µC/cm² at 600 kV/cm and a small leakage current density of 1 × 10^-5 A/cm² at -500 kV/cm. The considerable advantage of this Ti_2.5O₃/GaAs heterostructure provides an example of integrating other functional oxides for GaAs with suppressed ion diffusion. It also provides a platform for fabricating different electronic devices with higher reliability and performance.

Harnessing Plasmon-Induced Hot Carriers at the Interfaces With Ferroelectrics

This article reviews the scientific understanding and progress of interfacing plasmonic particles with ferroelectrics in order to facilitate the absorption of low-energy photons and their conversion to chemical fuels. The fundamental principles of hot carrier generation and charge injection are described for semiconductors interfaced with metallic nanoparticles and immersed in aqueous solutions, forming a synergistic juncture between the growing fields of plasmonically-driven photochemistry and semiconductor photocatalysis. The underlying mechanistic advantages of a metal-ferroelectric vs. metal-nonferroelectric interface are presented with respect to achieving a more optimal and efficient control over the Schottky barrier height and charge separation. Notable recent examples of using ferroelectric-interfaced plasmonic particles have demonstrated their roles in yielding significantly enhanced photocurrents as well as in the photon-driven production of molecular hydrogen. Notably, plasmonically-driven photocatalysis has been shown to occur for photon wavelengths in the infrared range, which is at lower energies than typically possible for conventional semiconductor photocatalysts. Recent results thus demonstrate that integrated ferroelectric-plasmonic systems represent a potentially transformative concept for use in the field of solar energy conversion.

Enhanced electrical properties in ferroelectric thin films on conductive Au–LaNiO3 nanocomposite electrodes via modulation of Schottky potential barrier

In this work, ferroelectric Pb(Zr,Ti)O₃ (PZT) thin films deposited on Au–LNO nanocomposite bottom electrode exhibited enhanced ferroelectric properties via modulation of Schottky potential barrier at the ferroelectric film/electrode interface.