Formation of Random Dark Envelope Solitons from Incoherent Waves

TL;DR

This paper experimentally demonstrates the formation of random dark solitons from incoherent spin-wave packets in a ferromagnetic film, revealing their random appearance and properties similar to coherent dark solitons.

Contribution

It introduces a new type of soliton, the random temporal dark soliton, formed from incoherent waves, expanding understanding of soliton phenomena in nonlinear media.

Findings

Dark solitons form randomly in time and space from incoherent waves.

Solitons can be gray or black, with multiple solitons observed in strong wave packets.

Despite randomness, solitons exhibit signatures of coherent dark solitons.

Abstract

This letter reports experimental results on a new type of soliton: the random temporal dark soliton. One excites an incoherent large-amplitude propagating spin-wave packet in a ferromagnetic film strip with a repulsive, instantaneous nonlinearity. One then observes the random formation of dark solitons from this wave packet. The solitons appear randomly in time and in position relative to the entire wave packet. They can be gray or black. For wide and/or very strong spin-wave packets, one also observes multiple dark solitons. In spite of the randomness of the initial wave packets and the random formation processes, the solitons show signatures that are found for conventional coherent dark solitons.