Low lattice thermal conductance obtained by controllable quasiperiodic long-range disorder in ternary atomic ribbons with rock-salt structure

Abstract

To achieve thermoelectric devices with high efficiency requires developing routes to modulate the vibrational properties of semiconductor materials that allow obtaining low lattice thermal conductance. Several efforts have been made to understand the thermal conduction of thermoelectric materials. In particular, semiconductors with rock-salt structure are promising for thermoelectric applications because of the possibility of modifying their thermal properties by composition and the huge quantity of compounds that can be built with this kind of structure. In this work, we investigate how the vibrational properties of ternary atomic ribbons with rock-salt structure can be controlled by Fibonacci long-range mass disorder structure. The study is performed through a real space analysis using the thermal Kubo–Greenwood formula and the Born interaction potential. The results show how the transmission of acoustical phonons with low frequency can be blocked by Fibonacci structures, leading to a progressive decrease of the lattice thermal conductance, which is favorable for thermoelectric applications.