The Role of an Isotropic Term in Governing the Temperature Range of the Incommensurate Phase

抄録

An isotropic term of the form QQ^* (∂Q⁄∂x)(∂Q^*⁄∂x) is taken into account in the Landau-type thermodynamic potential functional for the normal-incommensurate-commensurate phase transitions, and is shown to play quantitatively an important role in governing the temperature range of the incommensurate phase.