arXiv subjects

Chih-Ying Hsu

Publications and source records attributed to Chih-Ying Hsu.

3 recordsLinked to original sources

arXiv2026

Paramagnetically driven superconducting re-entrance in Eu-doped infinite layer nickelates

The breakthrough discovery of superconductivity in infinite-layer nickelates, and subsequently in several superconducting nickelates with more complex layered structures, capped a search spanning more than two decades and opened an entirely new field of research. Significant efforts aim to increase the critical temperature, to determine the electronic structure of the system, the underlying pairing mechanism, and the similarities between this system and cuprates - Ni1+ in infinite-layer nickelates being isoelectronic to Cu2+ in high-Tc cuprates. Here, we explore the unique role of magnetic rare earth ions in superconducting Eu-doped NdNiO2. We show that the field-induced re-entrant superconductivity which we evidence in this compound is the result of a delicate balance between the competing effects of the Eu2+ and Nd3+ ions. Our analyses of the extraordinary Hall effect and modeling of the superconducting critical fields demonstrate that the influence of these ions on magneto-transport is only felt when they are polarized by a magnetic field.

cond-mat.supr-con↗

arXiv2025

Curvature-Controlled Polarization in Adaptive Ferroelectric Membranes

In this study, we explore the ferroelectric domain structure and mechanical properties of PbTiO$_3$-based membranes, which develops a well-ordered and crystallographic-oriented ripple pattern upon release from their growth substrate. The ferrolectric domain structure of the PbTiO$_3$ layer was examined at various length scales using optical second harmonic generation, piezoresponse force microscopy, and scanning transmission electron microscopy. These methods reveal the presence of purely in-plane domains organized into superdomains at the crest of the ripples, while an in-plane/out-of-plane domain structure was observed in the flat regions separating the ripples, in agreement with phase-field simulations. The mechanical properties of the membrane were assessed using contact resonance force microscopy, which identified distinct mechanical behaviors at the ripples compared to the flat regions. This study shows that the physical properties of the ferroelectric layer in membranes can be locally controlled within an ordered array of ripples, with well-defined geometric characteristics.

cond-mat.mtrl-sci↗

arXiv2024

Electron-Beam Writing of Atomic-Scale Reconstructions at Oxide Interfaces

The epitaxial growth of complex oxides enables the production of high-quality films, yet substrate choice is restricted to certain symmetry and lattice parameters, thereby limiting the technological applications of epitaxial oxides. In comparison, the development of free-standing oxide membranes gives opportunities to create novel heterostructures by non-epitaxial stacking of membranes, opening new possibilities for materials design. Here, we introduce a method for writing, with atomic precision, ionically bonded crystalline material across the gap between an oxide membrane and a carrier substrate. The process involves a thermal pre-treatment, followed by localized exposure to the raster scan of a scanning transmission electron microscopy (STEM) beam. STEM imaging and electron energy-loss spectroscopy show that we achieve atomically sharp interface reconstructions between a 30 nm-thick SrTiO${_3}$ membrane and a niobium-doped SrTiO${_3}$(001)-oriented carrier substrate. These findings indicate new strategies for fabricating synthetic heterostructures with novel structural and electronic properties.

cond-mat.mtrl-sci↗