提交时间: 2017-05-02
摘要: The title compound, C18H28O3, was prepared by the reaction of 2,6-di-tert-butylphenol with methyl acrylate under basic conditions using dimethyl sulfoxide as the promoter. The structure of this antioxidant indicates significant strain between the ortho te
分类: 光学 >> 量子光学 提交时间: 2023-02-19
摘要: All-optical switching increasingly plays an important role in optical information processing. However, simultaneous achievement of ultralow power consumption, broad bandwidth and high extinction ratio remains challenging. We experimentally demonstrate an ultralow-power all-optical switching by exploiting chiral interaction between light and optically active material in a Mach-Zehnder interferometer (MZI). We achieve switching extinction ratio of 20.0(3.8) and 14.7(2.8) dB with power cost of 66.1(0.7) and 1.3(0.1) fJ/bit, respectively. The bandwidth of our all-optical switching is about 4.2 GHz. Our theoretical analysis shows that the switching bandwidth can, in principle, exceed 110 GHz. Moreover, the switching has the potential to be operated at few-photon level. Our all-optical switching exploits a chiral MZI made of linear optical components. It excludes the requisite of high-quality optical cavity or large optical nonlinearity, thus greatly simplifying realization. Our scheme paves the way towards ultralow-power and ultrafast all-optical information processing.
分类: 物理学 >> 核物理学 提交时间: 2023-06-20
摘要: The stellar (n, ) cross section data for the mass numbers around A 160 are of key importance to nucleosynthesis in the main component of the slow neutron capture process, which occurs in the thermally pulsing asymptotic giant branch (TPAGB). The new measurement of (n, ) cross sections for 159Tb was performed using the C6D6 detector system at the back streaming white neutron beam line (Back-n) of the China spallation neutron source (CSNS) with neutron energies ranging from 1 eV to 1 MeV. Experimental resonance capture kernels are reported up to 1.2 keV neutron energy with this capture measurement. Maxwellian-averaged cross sections (MACS) are derived from the measured 159Tb (n, ) cross sections at kT = 5100 keV and are in good agreement with the recommended data of KADoNiS-v0.3 and JEFF-3.3, while KADoNiS-v1.0 and ENDF-VIII.0 signifificantly overestimate the present MACS up to 40% and 20%, respectively. A sensitive test of the s-process nucleosynthesis is also performed with the stellar evolution code MESA. Signifificant changes in abundances around A 160 are observed between the ENDF/B-VIII.0 and present measured rate of 159Tb(n, ) 160Tb in the MESA simulation.