Reflectometry Study of the Pyroelectric Effect on Proton-Exchange Channel Waveguides in Lithium Niobate

This work is devoted to the study of the pyroelectric effect on the properties of optical waveguides formed in a lithium niobate crystal by proton exchange. In the present work, we studied the cessation effect of the radiation channeling during thermocycling of Y-splitters samples. We examined the spectral dependence of optical losses on the wavelength using an optical spectrum analyzer. The results demonstrate that in the range of 1530–1570 nm, all wavelengths are suppressed equally. The optical frequency domain reflectometry shows that the increase of optical losses is observed along the entire waveguide, but not only at the Y-splitting point, as supposed earlier.

Reflectometry Study of the Pyroelectric Effect on Proton-Exchange Channel Waveguides in Lithium Niobate

This work is devoted to the study of the pyroelectric effect on the qualities of optical waveguides formed in a lithium niobate crystal by proton exchange. In the present work, we investigated the cessation effect of the radiation channeling during thermocycling of Y-splitters samples. We examined the spectral dependence of optical losses on a wavelength using an optical spectrum analyzer. The results demonstrate that in the range of 1530–1570 nm, all wavelengths are suppressed equally. The optical reflectometry method in the frequency domain shows that the increase of optical losses is observed along the entire waveguide, but not only at the Y-distribution point, as supposed earlier.

Nonmetallic plasmonic heterostructures with multi-synergies on boosting hot electron generation for CO2 photoreduction

Constructing multi-physical effects on semiconductors is one new horizon to develop next-generation photocatalysts. Here we use pyroelectric black phosphorus (BP) to couple with nonmetallic plasmonic tungsten oxides (WO) forming a BP/WO heterostructures as photocatalysts to convert CO2 for CO under visible-near-infrared (Vis-NIR) light irradiation. Nonmetallic plasmonic heterostructures exhibit 26.1 µmol h− 1 g− 1 CO generation with a selectivity of 98 %, and which is 7- and 17-fold higher than those of plasmonic WO and pyroelectric BP, respectively. The interface P-O-W bonds in heterostructures are constructed to work as channels for electron transfer from BP to plasmonic WO. Moreover, the photothermal energy generated by SPR excitation on WO can make the temperature of heterostructures rapidly increasing from 24 to 86 oC in 10 min, triggering the pyroelectric BP for carriers to promote electron transfer. Multi-physical effects including plasmonic hot carriers and photothermal effect of WO, intrinsic band excitation and pyroelectric effect of BP and W-O-P bonds play synergistic roles on boosting hot electron generation for CO2 reduction. This work provides clear proofs to demonstrate that constructing multi-physical effects on semiconductors is one useful strategy to promote NIR-harvesting for artificial photosynthesis.

Pyroelectric-controlled bending of a self-trapped optical beam in a photorefractive iron doped lithium niobate crystal

We present the experimental demonstration of a self-trapped optical beam bending in a photorefractive Fe-doped lithium niobate (LN:Fe) crystal controlled by the pyroelectric effect. Formation of self-trapped beams with typical [Formula: see text]50[Formula: see text][Formula: see text]m diameter and large bending of [Formula: see text]140[Formula: see text][Formula: see text]m are depicted in a 1[Formula: see text]cm length LN:Fe crystal for a laser beam at 632.8[Formula: see text]nm wavelength and 0.5[Formula: see text]mW power with a 30∘C crystal temperature change. The self-trapped beam bending is opposite to the crystal [Formula: see text]-axis. The underlying physics is elaborated and numerical simulations are performed. The long-living waveguiding channels with controlled curvilinear trajectories are promising for optical information routing.

Perovskite Ferroelectric

The spectrums of properties exhibited by ferroelectric materials are dielectric, ferroelectric, piezoelectric and pyroelectric effect. This is the makes these materials to have a wide range of useful application. Infrared detectors are used pyroelectric effect of ferroelectric materials. It is used in nonvolatile memories due to have ferroelectric hysteresis. Its piezoelectric properties make them useful for actuator, radio frequency filter, sensor, and transducer. Ferroelectric capacitors are used, their good dielectric behavior. According to the necessity of the system they are available in different form such as single crystals, ceramics, thin film, and polymer, composite. The diversity of properties ferroelectric materials always attracted the attention of engineers and researchers. Size reduction of this material from micro to nanoscale established an enormous consideration to develop nanotechnology. Its vast use of different filed imposed the in detail research in adding to the development of processing and characterization method. This chapter will put some light on some fundamental principle of ferroelectricity, the list of perovskite materials and their application.

Enhanced pyrocatalysis of the pyroelectric BiFeO3/g-C3N4 heterostructure for dye decomposition driven by cold-hot temperature alternation

The BiFeO3/g-C3N4 heterostructure, which is fabricated via a simple mixing-calcining method, benefits the significant enhancement of the pyrocatalytic performance. With the growth of g-C3N4 content in the heterostructure pyrocatalysts from 0 to 25%, the decomposition ratio of Rhodamine B (RhB) dye after 18 cold-hot temperature fluctuation (25–65 °C) cycles increases at first and then decreases, reaching a maximum value of ∼94.2% at 10% while that of the pure BiFeO3 is ∼67.7%. The enhanced dye decomposition may be due to the generation of the internal electric field which strengthens the separation of the positive and negative carriers and further accelerates their migrations. The intermediate products in the pyrocatalytic reaction also have been detected and confirmed, which proves the key role of the pyroelectric effect in realizing the dye decomposition using BiFeO3/g-C3N4 heterostructure catalyst. The pyroelectric BiFeO3/g-C3N4 heterostructure shows the potential application in pyrocatalytically degrading dye wastewater.