Chapter Two - Magnetic Properties of Quasicrystals and Their Approximants

Abstract

Abstract An extensive review of the magnetic properties of quasicrystals (QCs) and their approximants (APs) is presented. It is shown that all known QCs are either paramagnets, diamagnets, or spin glasses, whereas some of their APs exhibit long-range antiferromagnetic order. The theoretically predicted existence of long-range magnetic order in QCs has yet to be found experimentally. The main difficulty in demonstrating the existence of the theoretically expected long-range magnetic order in QCs comes from the fact that the studied polygrain samples almost unavoidably contain magnetically ordered impurity phase(s). The importance of synthesizing single-grain QCs is emphasized. It is shown that in several QCs that are spin glasses, the spin-glass dynamics is fundamentally different from that expected in a canonical spin glass.