Nucleation and growth during the first order phase transition between U2D2 and CNAF 3He

The first order phase transition between two nuclear ordered antiferromagnetic solid 3He, namely U2D2-3He and CNAF-3He, was studied. Those two phases exist at the temperature below about 1mK and have the first order phase transition between them with the critical magnetic field BC1. We studied time and spatial evolution of the stable phase during the field-sweep induced phase transition near T=0. We found that the stable phase developed in two stages. During the first stage, many small seeds appeared throughout a crystal. Those nucleated seeds grew faster than the nucleation process, however terminated growing at some limited size due to a chemical potential loss by the latent heat release. The second stage was understood as the process of latent heat release through solid-liquid interface