Details

Autor(en) / Beteiligte

• Bozin, E S
• Xie, H
• Abeykoon, A M M
• Everett, S M
• Tucker, M G
• Kanatzidis, M G
• Billinge, S J L

Titel

Local Sn Dipolar-Character Displacements behind the Low Thermal Conductivity in SnSe Thermoelectric

Ist Teil von

• Physical review letters, 2023-07, Vol.131 (3), p.036101-036101, Article 036101

Ort / Verlag

United States: American Physical Society (APS)

Erscheinungsjahr

2023

Quelle

American Physical Society Journals

Beschreibungen/Notizen

• The local atomic structure of SnSe was characterized across its orthorhombic-to-orthorhombic structural phase transition using x-ray pair distribution function analysis. Substantial Sn displacements with a dipolar character persist in the high-symmetry high-temperature phase, albeit with a symmetry different from that of the ordered displacements below the transition. The analysis implies that the transition is neither order-disorder nor displacive but rather a complex crossover. Robust ferrocoupled SnSe intralayer distortions suggest a ferroelectriclike instability as the driving force. These local symmetry-lowering Sn displacements are likely integral to the ultralow lattice thermal conductivity mechanism in SnSe.