Lamellar fluctuations melt ferroelectricity
Date
28/07/2023Metadata
Show full item recordAbstract
We consider a standard Ginzburg-Landau model of a ferroelectric whose electrical polarization is coupled to gradients of elastic strain. At the harmonic level, such flexoelectric interaction is known to hybridize acoustic and optic phonon modes and lead to phases with modulated lattice structures that precede the state with spontaneously broken inversion symmetry. Here, we use the self-consistent phonon approximation to calculate the effects of thermal and quantum polarization fluctuations on the bare hybridized modes to show that such long-range modulated order is unstable at all temperatures. We discuss the implications for the nearly ferroelectric SrTiO3 and KTaO3, and we propose that these systems are melted versions of an underlying modulated state that is dominated by nonzero momentum thermal fluctuations except at the very lowest temperatures.
Citation
Guzmán-Verri , G G , Liang , C H & Littlewood , P B 2023 , ' Lamellar fluctuations melt ferroelectricity ' , Physical Review Letters , vol. 131 , no. 4 , 046801 . https://doi.org/10.1103/PhysRevLett.131.046801
Publication
Physical Review Letters
Status
Peer reviewed
ISSN
0031-9007Type
Journal article
Description
Funding: C.H.L. acknowledges support from NSF GRFP DGE-1746045, NSF INTERN, and DOE SCGSR. G.G.G.-V. acknowledges support from the Vice-rectory for Research at the University of Costa Rica under project No. 816-C1-601.Collections
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