We report on a novel technique to realize a waveguide optical isolator without using conventional magneto-optical materials and external magnets. The simulations are repeatedly performed using Beam Propagation Method (BPM) to confirm the accuracy. The simulation results show that the forward and backward propagations reach 2.54 and 15.68 dB, respectively.

Abstract In this paper, the shock train in isolator is taken as research object, and method of detecting leading edge position during self-excited oscillation forced studied by conducting wind tunnel test. A steady-state throttling system a fluctuating are designed to apply required back pressure downstream isolator. Then, four methods ratio method, difference standard deviation Fast Fourier Tr...

As the two dimensional version of the functional wavefront manipulation metamaterial, metasurface has become a research hot spot for engineering the wavefront at will with a subwavelength thickness. The wave scattered by the gradient metasurface, which is composed by the periodic supercells, is governed by the generalized Snell's law. However, the critical angle that derived from the generalize...

In this work we discuss the idea of one-way acoustic signal isolation in low dimensional nanoelectromechanical oscillators. We report a theoretical study showing that one-way conversion between in-phase and anti-phase vibrational modes of a double layer graphene nanoribbon is achieved by introducing spatio-temporal modulation of system properties. The required modulation length in order to reac...

We recently demonstrated a silicon (Si) waveguide-based device that performs mode conversion in only one direction (1). We called this effect nonreciprocal, a term that could be misleading as it implies that our device avoids Lorentz reciprocity. Indeed, either a magnetic or a time-dependent response is needed to convert our device into an optical isolator. An analysis of reciprocity of our asy...

The Hydraulic External Pre-Isolator (HEPI) is the first 6 degrees of freedom active seismic isolation system implemented at the Laser Interferometer Gravitational Wave Observatory (LIGO). Implementation was first completed at the LIGO Livingston Observatory (LLO) prior to LIGO’s 5th science run, successfully cutting down the disturbance seen by LLO’s suspended optics in the two most prominent s...

We introduce a new kind of cover called a normal isolator cover to characterize maximal Tychonoff spaces. Such a study is used to provide an alternative proof of an interesting result of Feng and Garcia-Ferreira in 1999 that every maximal Tychonoff space is extremally disconnected. Maximal tychonoffness of subspaces is also discussed.