arXiv subjects

L. Si

Publications and source records attributed to L. Si.

2 recordsLinked to original sources

arXiv2020

Robust skyrmion-bubble textures in SrRuO$_3$ thin films stabilized by magnetic anisotropy

Topological spin textures in an itinerant ferromagnet, SrRuO$_3$ is studied combining Hall transport measurements and numerical simulations. We observe characteristic signatures of the Topological Hall Effect associated with skyrmions. A relatively large thickness of our films and absence of heavy metal layers make the interfacial Dzyaloshinskii-Moriya interaction an unlikely source of these topological spin textures. Additionally, the transport anomalies exhibit an unprecedented robustness to magnetic field tilting and temperature. Our numerical simulations suggest that this unconventional behavior results from magnetic bubbles with skyrmion topology stabilized by magnetodipolar interactions in an unexpected region of parameter space.

cond-mat.str-el↗

arXiv2015

Surface effects on the Mott-Hubbard transition in archetypal V$_2$O$_3$

We present an experimental and theoretical study exploring surface effects on the evolution of the metal-insulator transition in the model Mott-Hubbard compound Cr-doped V$_2$O$_3$. We find a microscopic domain formation that is clearly affected by the surface crystallographic orientation. Using scanning photoelectron microscopy and X-ray diffraction, we find that surface defects act as nucleation centers for the formation of domains at the temperature-induced isostructural transition and favor the formation of microscopic metallic regions. A density functional theory plus dynamical mean field theory study of different surface terminations shows that the surface reconstruction with excess vanadyl cations leads to doped, and hence more metallic surface states, explaining our experimental observations.

cond-mat.str-el↗