We measure transient spin accumulation in Cu, Ag, and Au by time-resolved magneto-optical Kerr effect. The transient spin current is generated by ultrafast demagnetization of a ferromagnetic [Co/Pt] layer, and spin accumulates in an adjacent normal metal, Cu, Ag, or Au by spin diffusion. The magnitude of the Kerr rotation is described by an off-diagonal conductivity tensor that is proportional ...

In the framework of parallelism general relativity (PGR), the Dirac particle spin precession in the rotational gravitational field is studied. In terms of the equivalent tetrad of Kerr frame, we investigate the torsion axial-vector spin coupling in PGR. In the case of the weak field and slow rotation approximation, we obtain that the torsion axialvector has the dipole-like structure, but differ...

We present a new solution in Einstein-Maxwell theory which can be considered as the magnetized version of Kerr-Taub-NUT solution. Some properties spacetime are discussed. also compute entropy extremal black hole by using Kerr/CFT correspondence approach.

We study the dynamical behavior of the dilaton in the background of threedimensional Kerr-de Sitter space which is inspired from the low-energy string effective action. The Kerr-de Sitter space describes the gravitational background of a point particle whose mass and spin are given by 1−M and J and its curvature radius is given by l. In order to study the propagation of metric, dilaton, and Kal...

Using backwards ray tracing, we study the shadows of Kerr black holes with scalar hair (KBHSH). KBHSH interpolate continuously between Kerr BHs and boson stars (BSs), so we start by investigating the lensing of light due to BSs. Moving from the weak to the strong gravity region, BSs-which by themselves have no shadows-are classified, according to the lensing produced, as (i) noncompact, which y...

We demonstrate experimentally an all-optical switching operation using the Kerr effect in a silica toroid microcavity. Thanks to the small mode volume and high quality factor of the silica toroid microcavity, we achieved on-chip optical Kerr switching with an input power of 2 mW. This value is the smallest among all previously reported on-chip optical Kerr switches. We also show that this value...

The Kerr solution is defined by a null congruence which is geodesic and shear free and has a singular line contained in a bounded region of space. A generalization of the Kerr congruence for a nonstationary case is obtained. We find a nonstationary shear free geodesic null congruence which is generated by a given analytical complex world line. Solutions of the Einstein equations are analyzed. I...