Intrinsic localized mode and low thermal conductivity of PbSe

Abstract

Lead chalcogenides such as PbS, PbSe, and PbTe are of interest for their exceptional thermoelectric properties and strongly anharmonic lattice dynamics. Although PbTe has received the most attention, PbSe has a lower thermal conductivity despite being stiffer, a trend that prior first-principles calculations have not reproduced. Here, we use ab-initio calculations that explicitly account for strong anharmonicity to identify the origin of this low thermal conductivity as an anomalously large anharmonic interaction, exceeding in strength that in PbTe, between the transverse optic and longitudinal acoustic branches. The strong anharmonicity is reflected in the striking observation of an intrinsic localized mode that forms in the acoustic frequencies. Our work shows the deep insights into thermal phonons that can be obtained from ab-initio calculations that are not confined to the weak limit of anharmonicity.

18 pages, 5 figures

References in corpus (6)

• Giant Anharmonic Phonon Scattering in PbTe
• Entropy driven stabilization of energetically unstable crystal structures explained from first principles theory
• Thermal physics of the lead chalcogenides PbS, PbSe, and PbTe from first principles
• Intrinsic Localized Modes Observed in the High Temperature Vibrational Spectrum of NaI
• Ab Initio Phonon Dispersions for PbTe
• Lattice dynamics reveals a local symmetry breaking in the emergent dipole phase of PbTe

Cited by in corpus (3)

• Vibrational Effects in X-ray Absorption Spectra of 2D Layered Materials
• Uncertainty quantification in first-principles predictions of phonon properties and lattice thermal conductivity
• Thermal conductivity of intrinsic semiconductor at elevated temperature: role of four-phonon scattering and electronic heat conduction