activity
20172026
most citedSubterahertz collective dynamics of polar vortices

160 citations · 318 across the 14 of their papers we have counts for

collaborators

14 papers

cond-mat.mtrl-sci2026

Structural Phase Separation Couples to Charge-Density-Wave Formation in Kagome Metal FeGe

Boyang Zhao, Youngjun Ahn, Qinwen Deng +7

The intertwining of charge, spin, and lattice degrees of freedom underlies the emergent properties of correlated materials. A recent prominent example is the kagome metal FeGe, whi…

cond-mat.mtrl-sci2022★ 30 cited

Dynamical criticality of spin-shear coupling in van der Waals antiferromagnets

Faran Zhou, Kyle Hwangbo, Qi Zhang +15

The interplay between a multitude of electronic, spin, and lattice degrees of freedom underlies the complex phase diagrams of quantum materials. Layer stacking in van der Waals (vd…

cond-mat.mtrl-sci2022★ 5 cited

Optically Induced Picosecond Lattice Compression in the Dielectric Component of a Strongly Coupled Ferroelectric/Dielectric Superlattice

Deepankar Sri Gyan, Hyeon Jun Lee, Youngjun Ahn +13

Above-bandgap femtosecond optical excitation of a ferroelectric/dielectric BaTiO3/CaTiO3 superlattice leads to structural responses that are a consequence of the screening of the s…

cond-mat.mtrl-sci2022★ 15 cited

Ferro-rotational domain walls revealed by electric quadrupole second harmonic generation microscopy

Xiaoyu Guo, Rachel Owen, Austin Kaczmarek +9

Domain walls are ubiquitous in materials that undergo phase transitions driven by spontaneous symmetry breaking. Domain walls in ferroics and multiferroics have received tremendous…

cond-mat.mtrl-sci2021

Structural evidence for ultrafast polarization rotation in ferroelectric/dielectric superlattice nanodomains

Hyeon Jun Lee, Youngjun Ahn, Samuel D. Marks +16

Weakly coupled ferroelectric/dielectric superlattice thin film heterostructures exhibit complex nanoscale polarization configurations that arise from a balance of competing electro…

cond-mat.mes-hall2021★ 160 cited

Subterahertz collective dynamics of polar vortices

Qian Li, Vladimir A. Stoica, Marek Paściak +29

The collective dynamics of topological structures have been of great interest from both fundamental and applied perspectives. For example, the studies of dynamical properties of ma…

cond-mat.mtrl-sci2020★ 9 cited

Dynamic Tilting of Ferroelectric Domain Walls via Optically Induced Electronic Screening

Youngjun Ahn, Arnoud S. Everhardt, Hyeon Jun Lee +8

Optical excitation perturbs the balance of phenomena selecting the tilt orientation of domain walls within ferroelectric thin films. The high carrier density induced in a low-strai…

cond-mat.mtrl-sci2020★ 14 cited

Dynamical Scattering in Coherent Hard X-Ray Nanobeam Bragg Diffraction

A. Pateras, J. Park, Y. Ahn +5

Unique intensity features arising from dynamical diffraction arise in coherent x-ray nanobeam diffraction patterns of crystals having thicknesses larger than the x-ray extinction d…

cond-mat.mtrl-sci2020★ 2 cited

Stressor-Layer-Induced Elastic Strain Sharing in SrTiO3 Complex Oxide Sheets

J. A. Tilka, J. Park, Y. Ahn +3

A precisely selected elastic strain can be introduced in submicron-thick single-crystal SrTiO3 sheets using a silicon nitride stressor layer. A conformal stressor layer deposited u…

cond-mat.mes-hall2020★ 21 cited

Mesoscopic Elastic Distortions in GaAs Quantum Dot Heterostructures

Anastasios Pateras, Joonkyu Park, Youngjun Ahn +9

Quantum devices formed in high-electron-mobility semiconductor heterostructures provide a route through which quantum mechanical effects can be exploited on length scales accessibl…

cond-mat.mtrl-sci2019★ 4 cited

Role of temperature-dependent electron trapping dynamics in the optically driven nanodomain transformation in a PbTiO/SrTiO superlattice

Joonkyu Park, Youngjun Ahn, Jack A. Tilka +6

The spontaneously formed striped polarization nanodomain configuration of a PbTiO/SrTiO superlattice transforms to a uniform polarization state under above-bandgap illu…

cond-mat.mtrl-sci2019★ 9 cited

Non-thermal fluence threshold for femtosecond pulsed x-ray radiation damage in perovskite complex oxide epitaxial heterostructures

Hyeon Jun Lee, Youngjun Ahn, Samuel D. Marks +13

Intense hard x-ray pulses from a free-electron laser induce irreversible structural damage in a perovskite oxide epitaxial heterostructure when pulse fluences exceed a threshold va…

cond-mat.mes-hall2019★ 23 cited

Nanosecond Optically Induced Phase Transformation in Compressively Strained BiFeO3 on LaAlO3

Youngjun Ahn, Anastasios Pateras, Samuel D. Marks +9

Above-bandgap optical illumination induces a transformation from tilted tetragonal-like (T-like) and rhombohedral-like (R-like) phases to an untilted T-like phase in compressively…

cond-mat.mtrl-sci2017★ 26 cited

Photoinduced Domain Pattern Transformation in Ferroelectric/Dielectric Superlattices

Youngjun Ahn, Joonkyu Park, Anastasios Pateras +7

The nanodomain pattern in ferroelectric/dielectric superlattices transforms to a uniform polarization state under above-bandgap optical excitation. X-ray scattering reveals a disap…