Phase Transitions in Layered Systems

Tuneable Magnetic Phase Transitions in Layered CeMn2Ge2-xSix Compounds

The structural and magnetic properties of seven CeMn2Ge(2-x)Six compounds with x = 0.0-2.0 have been investigated in detail. Substitution of Ge with Si leads to a monotonic decrease of both a and c along with concomitant contraction of the unit cell volume and significant modifications of the magnetic states - a crossover from ferromagnetism at room temperature for Ge-rich compounds to antiferr...

Phase Transitions in Multicomponent Systems

Consider a system with n components (different types of molecules) with r phases in equilibrium. The state of each phase is defined by P, T and then (n− 1) concentration variables in each phase. The phase equilibrium at given P, T is defined by the equality of n chemical potentials between the r phases. Thus there are n(r − 1) constraints on (n− 1)r + 2 variables. This gives the Gibbs phase rul...

Phase Transitions in Random Systems

These lectures discuss the theory of phase transitions and critical phenomena in random systems. First a discussion is given of the basic principles, including averaging, the concept of frustration, and the Harris criterion for deciding whether weak randomness is relevant. This is followed by the study of several examples: weakly random ferromagnets, the percolation problem, the random eld prob...

Phase Transitions in Nonequilibrium Systems

Collective phenomena in systems far from thermal equilibrium have been a subject of extensive studies in recent years. Usually these systems are driven out of equilibrium by external fields, such as electric field in the case of conductors, pressure gradient in the case of fluids, temperature gradient in the case of heat conductors, chemical potential gradient in the case of growth problems and...

Helical edge states and topological phase transitions in phononic systems using bi-layered lattices