Dr. Jaka Pišljar: Confinement driven transitions in chiral liquid crystal half-skyrmion phases

The 3D structure of crystalline chiral blue phases confined to layers of thickness below the size of a single unit cell, transforms into a quasi-2D phase of condensed chiral half-skyrmions, analogoues to Bloch skyrmions in magnetic systems. In this seminar, I will present two distinct frustration-related phenomena directly observed in this system.

First, I will summarize our recently published results on the cooling phase transition into the half-skyrmion phase in sub-100 nm layers, where we find extremely slowed down pretransitional fluctuations. Second part will focus on the ongoing work on a transition between hexagonally ordered crystalline and liquid states, in the condensed phase of half-skyrmions. The transition is driven by changing the confining thickness and the characteristic fusion-fission dynamics of the half-skyrmions. A simillar phase transition has recently been reported for magnetic skyrmions.