In-line control of polarization sensitivity for fiber-optic biconical fused single-mode couplers

The possibility to use the fiber-optic coupler input port as the polarization vector rotator of linearly polarized light introduced therein to control the coupler polarization sensitivity has been demonstrated in experiment. The experimental dependences of the polarization vector rotation at the fiber coil output on the fiber straightening extent are presented.Экспериментально продемонстрирована возможность использования входного порта волоконно-оптического разветвителя в качестве вращателя вектора поляризации вводимого в него линейно поляризованного света для контроля поляризационной чувствительности разветвителя. Приведены экспериментальные зависимости угла поворота вектора поляризации света на выходе из витка волокна от степени выпрямления волокна.Експериментально продемонстровано можливість використання вхідного порту волоконно-оптичного розгалужувана як обертача вектора поляризації лінійно поляризованого світла, яке вводиться в порт, для контролю поляризаційної чутливості розгалужувана. Наведено експериментальні залежності кута повороту вектора поляризації світла на виході з витка волокна від ступеню випрямлення волокна

Parametric interaction in the Terfenol-D based magnetostrictive composite and nickel ferrite

The parametric interaction between electomagnetic pumping field and magnetoelastic oscillations in the Terfenol-D based composite has been studied. An original high-sensitivity expiremental technique to study the pulse pumping influence on the decay of magnetoelastic oscillations in the sub-threshold parametric mode in described. The results obtained for the Terfenol-D based composite are compared with data for the polycrystalline nickel ferrite

Valley polarization of trions in monolayer MoSe2 interfaced with bismuth iron garnet

Interfacing atomically thin van der Waals semiconductors with magnetic substrates enables additional control on their intrinsic valley degree of freedom and provides a promising platform for the development of novel valleytronic devices for information processing and storage. Here we study circularly polarized photoluminescence in heterostructures of monolayer MoSe2 and thin films of ferrimagnetic bismuth iron garnet (BIG). We observe strong emission from charged excitons with circular polarization opposite to that of the pump and demonstrate contrasting response to left and right circularly polarized excitation, associated with finite out-of-plane magnetization in the substrate. We propose a theoretical model accounting for magnetization-induced imbalance of charge carriers in the two valleys of MoSe2, as well as for valley-switching scattering from B to A excitons and fast formation of trions with extended valley relaxation times, which shows excellent agreement with the experimental data. Our results establish monolayer MoSe2 interfaced with BIG as a promising system for valley control of charged excitons