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Tuning Coherent-Phonon Heat Transport in LaCoO₃/SrTiO₃ Superlattices.

ABSTRACT: Accessing the regime of coherent phonon propagation in nanostructures opens enormous possibilities to control the thermal conductivity in energy harvesting devices, phononic circuits, etc. In this paper we show that coherent phonons contribute substantially to the thermal conductivity of LaCoO₃/SrTiO₃ oxide superlattices, up to room temperature. We show that their contribution can be tuned through small variations of the superlattice periodicity, without changing the total superlattice thickness. Using this strategy, we tuned the thermal conductivity by 20% at room temperature. We also discuss the role of interface mixing and epitaxial relaxation as an extrinsic, material dependent key parameter for understanding the thermal conductivity of oxide superlattices.

SUBMITTER: Bugallo D

PROVIDER: S-EPMC8686111 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Tuning Coherent-Phonon Heat Transport in LaCoO3/SrTiO3 Superlattices.

Bugallo D D Langenberg E E Carbó-Argibay E E Varela Dominguez Noa N Fumega A O AO Pardo V V Lucas Irene I Morellón Luis L Rivadulla F F

The journal of physical chemistry letters 20211207 49

Accessing the regime of coherent phonon propagation in nanostructures opens enormous possibilities to control the thermal conductivity in energy harvesting devices, phononic circuits, etc. In this paper we show that coherent phonons contribute substantially to the thermal conductivity of LaCoO3/SrTiO3 oxide superlattices, up to room temperature. We show that their contribution can be tuned through small variations of the superlattice periodicity, without changing the total ...[more]

PMID: 34875171

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