Ferroelectric materials manifest unique dielectric, ferroelastic, and piezoelectric properties. A targeted design of ferroelectrics at the nanoscale is not only of fundamental appeal but holds the highest potential for applications. Compared to two-dimensional nanostructures such as thin films and superlattices, one-dimensional ferroelectric nanowires are investigated to a much lesser extent. Here, we reveal a variety of the topological polarization states, particularly the vortex and helical chiral phases, in loaded ferroelectric nanowires, which enable us to complete the strain–temperature phase diagram of the one-dimensional ferroelectrics. These phases are of prime importance for optoelectronics and quantum communication technologies.

The past decade’s discovery of topological excitations in nanoscale ferroelectrics has turned the prevailing view that the polar ground state in these materials is uniform. However, the systematic understanding of the topological polar structures in ferroelectrics is still on track. Here we study stable vortex-like textures of polarization in the nanocylinders of ferroelectric PbTiO _3 3 , arising due to the competition of the elastic and electrostatic interactions. Using the phase-field numerical modeling and analytical calculations, we show that the orientation of the vortex core with respect to the cylinder axis is tuned by the geometrical parameters and temperature of the system.

The control of ferroelectric topological phases in ultrathin films is central to the development of next-generation nanoelectronic devices. While epitaxial strain is widely used to tune polarization states, its applicability is inherently limited to substrate-bound systems. Here, we show that surface tension becomes a key mechanical factor in freestanding ferroelectric films, governing phase stability and the emergence of topological polarization textures. Using a thermodynamic free energy framework, we show that surface tension induces effective compressive stress in freestanding films, strongly influencing both uniform and topological polarization states. Surface tension also drives large-scale morphological instabilities, reshaping phase behavior in the ferroelectric regime. Our results reveal surface tension as a robust, substrate-independent mechanism for engineering polarization states in freestanding films, creating new opportunities for flexible, strain-free ferroelectric devices.

A quantum paraelectric SrTiO₃ is a material situated in close proximity to a quantum critical point (QCP) of ferroelectric transition in which the critical temperature to the ferroelectric state is suppressed down to 0 K. However, the understanding of the behavior of the phase transition in the vicinity of this point remains challenging. Using the concentration x of Pb in solid solution Sr_1−xPb_xTiO₃ (PSTx) as a tuning parameter and applying the combination of Raman and dielectric spectroscopy methods, we approach the QCP in PSTx and study the interplay of classical and quantum phenomena in the region of criticality. We obtain the critical temperature of PSTx and the evolution of the temperature-dependent dynamical properties of the system as a function of x to reveal the mechanism of the transition. We show that the ferroelectric transition occurs gradually through the emergence of the polar nanoregions inside the non-polar tetragonal phase with their further expansion on cooling. We also study the ferroelastic cubic-to-tetragonal structural transition, occurring at higher temperatures, and show that its properties are almost concentration-independent and not affected by the quantum criticality.

Surface tension phenomena acquire significance at the nanoscale due to the pivotal influence of surfaces on properties of confined nanosystems. Yet, surface tension is often omitted when addressing the properties of nanostructured solid materials. Here, we reveal the impact of surface tension on polarization states in ferroelectric nanorods, demonstrating the surface-tension-tailored occurrence of distinct vortex and uniform phases with different spatial topologies. We study how the emergence of these states is tuned by temperature and geometry of the system and provide the radius-temperature phase diagram in exemplary lead titanate ferroelectric nanorods. The discovered surface tension effects allow for the deliberate design and tuning of topological phases in ferroelectric nanorods for their further implementation into nanoelectronic devices and multilevel logic memory units in neuromorphic computing circuits.