Optical poling of a quantum ferroelectric metal across the order-disorder phase transition
Abstract
Electron-doped strontium titanate has emerged as a prototypical quantum ferroelectric metal. It provides a fertile ground to explore how ferroelectric instability intertwined with itinerant electrons creates quantum phenomena, including unconventional superconductivity. Despite extensive studies, the microscopic origin of the ferroelectric transition remains unsettled, with distinct interpretations based on displacive mechanism driven by soft mode and order-disorder alignment of local dipoles. In particular, the local dipoles form nanoscale, spatially heterogeneous clusters, termed polar nanoregions, posing a significant challenge for probing or manipulating them. Here, using rotational anisotropy second harmonic generation, a symmetry-resolved probe, we quantify the orientational statistics of polar nanoregions in dilute electron-doped Sr0.95Ba0.05Ti1−xNbxO3. By tracking the alignment and meltdown of polar nanoregions in thermal cycles, we unambiguously demonstrate the order-disorder nature of the ferroelectric transition. We further show that, above transition temperature, femtosecond optical fields enable deterministic control of otherwise disordered polar nanoregions, realizing reversible write and readout of polar textures on ultrafast timescales. Our findings provide new insight into ferroelectric instability and establish an all-optical route of controlling polar metal systems where conventional electrical approaches are not feasible.
Versions
Related
- Ferroelectric Switching in x-cut MgO-doped Thin-Film Lithium Niobate: Implications for Periodic Poling and Domain-Wall Electronics
- Noise suppression of quantum frequency conversion in thin-film lithium niobate waveguides via adapted poling
- Interaction induced flattening of optical transition quantum geometry
- Unusual phase coexistence regime across the ferroelectric - paraelectric transition
- Holonomy Analysis of Optical-polarization Temperature Trajectories in Stress-induced Ferroelectric SrTiO3
BibTeX
@misc{kandil2026optical,
title = {{Optical poling of a quantum ferroelectric metal across the order-disorder phase transition}},
author = {Mohamed Kandil and Yasuhide Tomioka and Yafei Ren and Ryan Comes and Isao H. Inoue and Wencan Jin},
howpublished = {arXiv},
year = {2026},
month = aug,
doi = {10.48550/arxiv.2608.18427},
eprint = {2608.18427},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.18427},
}
RIS
TY - UNPB
TI - Optical poling of a quantum ferroelectric metal across the order-disorder phase transition
AU - Mohamed Kandil
AU - Yasuhide Tomioka
AU - Yafei Ren
AU - Ryan Comes
AU - Isao H. Inoue
AU - Wencan Jin
PY - 2026
DA - 2026/08/19
PB - arXiv
DO - 10.48550/arxiv.2608.18427
UR - https://arxiv.org/abs/2608.18427
AB - Electron-doped strontium titanate has emerged as a prototypical quantum ferroelectric metal. It provides a fertile ground to explore how ferroelectric instability intertwined with itinerant electrons creates quantum phenomena, including unconventional superconductivity. Despite extensive studies, the microscopic origin of the ferroelectric transition remains unsettled, with distinct interpretations based on displacive mechanism driven by soft mode and order-disorder alignment of local dipoles. In particular, the local dipoles form nanoscale, spatially heterogeneous clusters, termed polar nanoregions, posing a significant challenge for probing or manipulating them. Here, using rotational anisotropy second harmonic generation, a symmetry-resolved probe, we quantify the orientational statistics of polar nanoregions in dilute electron-doped Sr_0.95Ba_0.05Ti_1−xNb_xO_3. By tracking the alignment and meltdown of polar nanoregions in thermal cycles, we unambiguously demonstrate the order-disorder nature of the ferroelectric transition. We further show that, above transition temperature, femtosecond optical fields enable deterministic control of otherwise disordered polar nanoregions, realizing reversible write and readout of polar textures on ultrafast timescales. Our findings provide new insight into ferroelectric instability and establish an all-optical route of controlling polar metal systems where conventional electrical approaches are not feasible.
ER -