Flexoelectricity and thermal fluctuations of lipid bilayer membranes: Renormalization of flexoelectric, dielectric, and elastic properties

摘要

Thermal fluctuations renormalize the bending elasticity of lipid bilayers. This well-studied effect is ancornerstone in the study of several membrane biophysical phenomena. Analogously, nearly all membranesnare endowed with an electromechanical coupling called flexoelectricity that admits membrane polarization duento curvature changes. Flexoelectricity is found to be important in a number of biological functions, includingnhearing, ion transport, and in some situations where mechanotransduction is necessary. Very little is knownnabout the interplay between thermal fluctuations and flexoelectricity. In this work, we explore how the apparentnflexoelectricity is altered due to thermal fluctuations and, further, how the elastic and dielectric properties arenrenormalized due to flexoelectricity.We find that the apparent bending rigidity is softened by flexoelectricity andndiscuss the ramifications for interpreting existing experimental work.