Mode scrambler

About: Mode scrambler is a research topic. Over the lifetime, 896 publications have been published within this topic receiving 13595 citations.

Wavelength-selective switch with direct few mode fiber integration.

Abstract: The first realization of a wavelength-selective switch (WSS) with direct integration of few mode fibers (FMF) is fully described. The free-space optics FMF-WSS dynamically steers spectral information-bearing beams containing three spatial modes from an input port to one of nine output ports using a phase spatial light modulator. Sources of mode dependent losses (MDL) are identified, analytically analyzed and experimentally confirmed on account of different modal sensitivities to fiber coupling in imperfect imaging and at spectral channel edges due to mode clipping. These performance impacting effects can be reduced by adhering to provided design guidelines, which scale in support of higher spatial mode counts. The effect on data transmission of cascaded passband filtering and MDL build-up is experimentally investigated in detail.

Coherent light source and optical device

Abstract: High power output can be easily obtained from a wide stripe laser, however, since its transverse mode is a multimode and an efficiency of coupling with a single mode waveguide and a single mode fiber is low, there have been problems in application to high-coherence devices. An oscillation mode of a semiconductor laser can be fixed to a single mode by feeding back beams projected from the wide stripe semiconductor laser to an active layer of the semiconductor laser, after having the beams permeate a mode transducer and a wavelength selecting filter.

Characterization of Mode Coupling in Few-Mode FBG With Selective Mode Excitation

Abstract: We present the results on fabrication and the characterization of few-mode fiber Bragg gratings (FM-FBGs) inscribed in two mode and four mode step-index fibers. Under the conditions of selective input mode launching, coupling between specific modes of interest can be selectively excited and the self-coupling and cross-coupling properties at the associated resonant wavelengths can be clearly identified and verified by observing the reflected mode intensity profiles. Such FM-FBGs can potentially be used as reflective mode-converters for mode division multiplexed data transmission systems.

A novel differential mode rejection network for conducted emissions diagnostics

Abstract: A differential mode rejection network (DMRN), a device which separates common mode noise from differential mode noise in a line impedance stabilization network (LISN)-based conducted emissions setup, is described. Although it is not a filter, its function is analogous to that of a filter. The DMRN filters out differential mode, and passes common mode unfiltered. The differential mode is attenuated by more than 50 dB, and the common mode noise is attenuated by less than 4 dB. Applications of the DMRN are discussed for filter design and troubleshooting, and electromagnetic interference source suppression is briefly described. Mathematical analysis and hardware implementation of the devices are explained. >

Weakly-Guiding Mode-Selective Fiber Couplers

Abstract: This paper presents analytical descriptions of the behavior of weakly-guiding/weakly-coupled mode-selective fiber couplers, based on coupled-mode theory. Mode-selective couplers rely on the phase-matching of a higher-order mode in one fiber with the fundamental mode of a second, closely-positioned fiber. Their behavior is shown to be highly-dependent on the principle and azimuthal mode numbers of the higher-order mode, as well as its spatial-orientation. Zero coupling is shown to be possible for an asymmetric higher-order mode even when there is perfect phase-matching. The theory is also numerically simulated, and could assist in the future design of efficient mode-selective couplers for a wide range of optical communications and sensor systems.