Quantifying antiferromagnetism in a topologically ordered tetratic 
TYPE  Student Seminar 
Speaker:  Jalal Abu Ahmad Wawi 
Affiliation:  Technion 
Date:  08.05.2024 
Time:  13:30  15:00 
Location:  Lidow Nathan Rosen (300) 
Abstract:  While it is known that the phase transition from solid to liquid phase is a first order phase transition, in twodimensions there exists a scenario where the melting of a crystal goes through two continuous phase transitions. These transitions follow the KosterlitzThoulessHalperin In a square lattice the intermediate phase that resides between the solid and the liquid phase is called the tetratic phase, at this phase the lattice contains areas with dislocation pairs that are bound together, so that to an observer the lattice looks like a perfect square lattice with areas that contain defects which break the bipartiteness of the lattice. In the special case where the square lattice is strongly antiferromagnetic, the antiferromagnetic nature is “preserved” throughout the melting process. After applying some rules that solve the problem of the broken local bipartiteness in dislocation areas, we have successfully shown the existence of longrange antiferromagnetis order in the tetratic phase.
