Phys.org December 13, 2023
Quantum fluctuations (QFs) caused by zero-point phonon vibrations (ZPPVs) are known to prevent the occurrence of polar phases in bulk incipient ferroelectrics down to 0 K. On the other hand, little is known about the effects of QFs on the recently discovered topological patterns in ferroelectric nanostructures. A team of researchers in the US (University of Arkansas, Fayetteville, Lonestar College, Texas) has shown how QFs affect the topology of several dipolar phases in ultrathin Pb(Zr0.4Ti0.6)O3 (PZT) films. They showed that the ZPPVs do not suppress polar patterns but rather stabilize the labyrinth, bimeron and bubble phases within a wider range of bias field magnitudes. They also found that quantum fluctuations induced a quantum critical point (QCP) separating a hexagonal bubble lattice from a liquid-like state characterized by spontaneous motion, creation, and annihilation of polar bubbles at cryogenic temperatures. The quantum melting is associated with anomalous physical response, as, e.g., demonstrated by a negative longitudinal piezoelectric coefficient… read more. Open Access TECHNICAL ARTICLE
Topological patterns for different Trotter Numbers. Credit: Nature Communications volume 14, Article number: 7874 (2023)