Enhanced forward stimulated Brillouin scattering in silicon photonic slot waveguide Bragg grating

We study the forward stimulated Brillouin scattering process in a suspended silicon slot waveguide Bragg grating. Full-vectorial formalism is applied to analyze the interplay of electrostriction and radiation pressure. We show that radiation pressure is the dominant factor in the proposed waveguide. The Brillouin gain strongly depends on the structural parameters and the maximum value in the order of 106 W−1 m−1 is obtained in the slow light regime, which is more than two orders larger than that of the stand-alone strip and slot waveguides

All-optical non-volatile tuning of an AMZI-coupled ring resonator with GST phase-change material

We present a Ge2Sb2Te5 (GST)-integrated ring resonator with the tuning enabled by an all-optical phase change of GST using a sequence of optical pulses. The tuning is non-volatile and repeatable, with no static power consumption due to the “self-holding” feature of the GST phase-change material. The 2 μm long GST can be partially crystallized by controlling the number of pulses, increasing the tuning freedom. The coupling between the ring resonator and the bus waveguide is based on an asymmetric Mach–Zehnder interferometer. The coupling strength is wavelength-dependent, so that an optimal wavelength can be selected for the probe light to get more than 20 dB transmission contrast between the amorphous and crystalline GST states

Comparison of different measures for quantum discord under non-Markovian noise

Two geometric measures for quantum discord were recently proposed by Modi et al. [Phys. Rev. Lett. 104, 080501 (2010)] and Dakic et al. [Phys. Rev. Lett. 105, 190502 (2010)]. We study the similarities and differences for total quantum correlations of Bell-diagonal states using these two geometry-based quantum discord and the original quantum discord. We show that, under non-Markovian dephasing channels, quantum discord and one of the geometric measures stay constant for a finite amount of time, but not the other geometric measure. However, all the three measures share a common sudden change point. Our study on critical point of sudden transition might be useful for keeping long time total quantum correlations under decoherence.Comment: 10 pages, 3 figures submitted for publicatio

A Multifunctional Gelatin-Quaternary Ammonium Copolymer Exhibiting Superior Anionic Dye Adsorption for Efficient Emission Reduction in Leather Tanning Process

Leather wastewater is one of the most polluting industrial emissions. An in-situ, green, and innovative strategy that limits dye emissions is required to replace subsequent waste management. A novel cationic protein with a high quaternary ammonium degree was designed and synthesized. The results show that at concentrations ranging from 3 to 15 wt%, this cationic protein rapidly and completely adsorbs Direct Purple N and Acid Black 24 within 5 min. A remarkable efficiency in removing Acid Red 73, Acid Golden G, Acid Lake Blue A, Acid Green, and Acid Orange II, with >96% removal rates, was achieved. The cationic protein was most accurately represented by the pseudo-second-order kinetic model. Acid Orange II (2000 mg L-1) and 15 wt% cationic protein were used in an actual tanning process. The residual concentration of Acid Orange II in the wastewater was 23.1 mg L-1. These results reflect that the emission reduction targets have been effectively achieved

Cross-domain recommendation with probabilistic knowledge transfer

© Springer Nature Switzerland AG 2018. Recommender systems have drawn great attention from both academic and practical area. One challenging and common problem in many recommendation methods is data sparsity, due to the limited number of observed user interaction with the products/services. To alleviate the data sparsity problem, cross-domain recommendation methods are developed to share group-level knowledge in several domains so that recommendation in the domain with scarce data can benefit from domains with relatively abundant data. However, divergence exists in the data of similar domains so that the extracted group-level knowledge is not always suitable to be applied in the target domain, thus recommendation accuracy in the target domain is impaired. In this paper, we propose a cross-domain recommendation method with probabilistic knowledge transfer. The proposed method maintain two sets of group-level knowledge, profiling both domain-shared and domain-specific characteristics of the data. In this way users’ mixed preferences can be profiled comprehensively thus improves the performance of the cross-domain recommender systems. Experiments are conducted on five real-world datasets in three categories: movies, books and music. The results for nine cross-domain recommendation tasks show that our proposed method has improved the accuracy compared with five benchmarks

Effect of cold rolling process on texture evolution of gradient microstructure in Fe-3,0 % Si non-oriented silicon steel

This study focused on the microstructure evolution of non-oriented Fe-3,0 %Si steel used in the core of new energy vehicle drive motor. An hot band and a sample normalized at 800 °C for 10 min were subjected to a moderate cold rolling and an annealing treatment. The results show that the initial hot band has gradient microstructure. After normalizing, the surface is consisted of fine recrystallized grains, the central layer has elongated α-fiber and γ-fiber grains, the subsurface shows a mixed grain structure with strong Goss texture. After cold rolling with a thickness reduction of 40 %, α-fiber and γ-fiber textures are strengthened, and unstable Goss texture disappears. After annealing at 700 °C for 5 min, gradient recrystallization occurs and γ-fiber texture is weakened. The central and subsurface layers show frequently nucleation phenomena in the grain interior and grain boundaries, resulting in strong Ѳ-fiber, α*-fiber and Goss components

Effect of cold rolling process on texture evolution of gradient microstructure in Fe-3,0 % Si non-oriented silicon steel

This study focused on the microstructure evolution of non-oriented Fe-3,0 %Si steel used in the core of new energy vehicle drive motor. An hot band and a sample normalized at 800 °C for 10 min were subjected to a moderate cold rolling and an annealing treatment. The results show that the initial hot band has gradient microstructure. After normalizing, the surface is consisted of fine recrystallized grains, the central layer has elongated α-fiber and γ-fiber grains, the subsurface shows a mixed grain structure with strong Goss texture. After cold rolling with a thickness reduction of 40 %, α-fiber and γ-fiber textures are strengthened, and unstable Goss texture disappears. After annealing at 700 °C for 5 min, gradient recrystallization occurs and γ-fiber texture is weakened. The central and subsurface layers show frequently nucleation phenomena in the grain interior and grain boundaries, resulting in strong Ѳ-fiber, α*-fiber and Goss components

Silicon microring resonators tuned with GST phase change material

We investigate silicon microring resonators embedded with Ge2Sb2Te5. The phase change is induced all optically by using a sequence of optical pulses. The tuning is non-volatile and repeatable, which can be employed for optical trimming