Equilibrium mode distribution

About: Equilibrium mode distribution is a research topic. Over the lifetime, 928 publications have been published within this topic receiving 14939 citations.

Spatial-mode conversion using random diffuser and spatial light modulator for reduction of modal crosstalk

Abstract: The mode-division multiplexing (MDM) technique enables the transmission of multiple signals within a multi-mode fiber (MMF) or a few-mode fiber (FMF). To construct an efficient and flexible MDM network in the same way as a wavelength-division multiplexing network, a mode conversion method with low modal crosstalk is required for switching between arbitrary spatial modes. However, in general, modal crosstalk is strongly dependent on the intensity pattern before mode conversion, and it is increased particularly for higher order modes. In order to reduce modal crosstalk, we propose a method using a random diffuser and a spatial light modulator (SLM). In the proposed method, firstly, the input spatial mode is dispersed uniformly by the random diffuser. Subsequently, the diffused phase distribution is canceled and converted into the desired spatial mode by the SLM, which displays phase difference between desired and diffused modes. Consequently, every spatial mode can be evenly converted into a desired mode. Here, we numerically simulate and confirm that the proposed method can reduce modal crosstalk compared to the conversion method without the random diffuser.

Technique for measuring mode power of two-mode fiber

Abstract: In a previous paper, we proposed a simple method for measuring the mode excitation ratio in a two-mode fiber (TMF). Here, we experimentally investigate the applicability of the proposed method and also propose an alternative formulation to reduce experimental error.

Dynamic Mode Group Equalization Filter and Variable Optical Attenuator for Few Mode Fibers

Abstract: Variable optical attenuation for few-mode fibers is presented, utilizing an amplitude spatial light modulator. -28dB uniform attenuation and 10dB differential mode equalization is demonstrated, potentially gain-balancing mode dependent amplification

Mode excitation ratio measurement of a two-mode fiber with offset fusion splice

Abstract: We experimentally investigate the mode excitation ratio of a two-mode fiber (TMF) based on the bending method. TMFs with three different kinds of mode excitation ratio of LP11 mode to LP01 are prepared and successfully measured by our present method.

Optical mode conversion analysis in double magnetic layers by magnetostatic surface waves

Abstract: Optical transverse-electric-transverse-magnetic (TE-TM) mode conversion by magnetooptic effect induced by magnetostatic surface waves (MSSWs) is analyzed. A typical MSSW waveguide has a thick layer for the convenient excitation of MSSWs. However, the waveguide is not a single-mode waveguide but is multimode for the optical wavelength. Such a waveguide is not suitable for optical devices because the conversion efficiency decreases due to coupling between higher modes. A multilayer waveguide constructed with the double magnetic layers, in which only the optical fundamental mode propagates and which improves the characteristics of optical mode conversion is proposed. An efficiency of 100% is achieved over an interaction length of about 1.0 cm for the applied microwave power density of a few milliwatts per millimeter. >