{"id":34,"date":"2026-03-05T19:18:24","date_gmt":"2026-03-05T22:18:24","guid":{"rendered":"https:\/\/www.ufrgs.br\/newinctmqa\/?page_id=34"},"modified":"2026-03-09T22:24:38","modified_gmt":"2026-03-10T01:24:38","slug":"high001","status":"publish","type":"page","link":"https:\/\/www.ufrgs.br\/newinctmqa\/high001\/","title":{"rendered":"High001"},"content":{"rendered":"\n

Highlights<\/h2>\n\n\n\n
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Unveiling the structure\u2013magnetism interplay in the ferrimagnetic pyrochlore Gd2<\/sub>CrSbO7<\/sub> with significant cryo\u2013magnetocaloric performance<\/strong><\/h4>\n\n\n\n
Communications Materials, 7, 6 (2026)<\/strong><\/h6>\n\n\n\n

R. S. Silva Jr, J. E. Rodrigues, C. Santos, Ch Sahle, F. Serrano-S\u00e1nchez, H. L. Andersen, J. Gainza, A. Skorynina, N. Biskup, N. M. Nemes, E C. Passamani, J. L. Mart\u00ednez, N. S. Ferreira & J. A. Alonso<\/p>\n\n\n\n

In this work, with participation of Prof. Edson C. Passamani (UFES) and Prof. Nilson S. Ferreira (UFS)<\/strong>, the ferrimagnetic pyrochlore Gd\u2082CrSbO\u2087 is investigated via diffraction, X-ray Raman spectroscopy, EXAFS, magnetization measurements, and first-principles calculations. The material exhibits 4f\u20133d exchange-driven ferrimagnetism, a Griffiths-like phase, and a Schottky anomaly. It achieves \u0394S\u2098 \u2248 21 J\/kg\u00b7K and refrigerant capacity \u2248 430 J\/kg (0\u20137 T), comparable to benchmark cryogenic refrigerants but using earth-abundant elements. The main contributions are the introduction of a competitive, low-cost magnetocaloric material and advanced understanding of structure\u2013frustration\u2013magnetism interplay in mixed pyrochlore oxides.<\/p>\n\n\n\n

Correspondence: nilson@academico.ufs.br<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Quantum Geometry and the Electric Magnetochiral Anisotropy in Noncentrosymmetric Polar Media<\/strong><\/h4>\n\n\n\n
Physical Review Letters, 135, 106602, (2025)<\/strong><\/h6>\n\n\n\n

Pierpaolo Fontana, Victor Velasco, Chang Niu, Peide D. Ye, Pedro V. Lopes, Kaio E. M. de Souza, Marcus V.\u2009O. Moutinho, Caio Lewenkopf and Marcello B. Silva Neto<\/p>\n\n\n\n

This work, with participation of Prof. Marcello B. S. Neto (UFRJ), connects electric magnetochiral anisotropy (eMChA) to the quantum metric of Bloch states. Using semiclassical transport theory including quantum metric dipole corrections, and second-harmonic transport measurements in 2D tellurium films, the authors demonstrate universal scaling \u03b3(V) \u223c V\u207b\u2075\u141f\u00b2 under gate tuning. They also identify quantum geometry as the microscopic origin of eMChA, unifying nonreciprocal transport and band topology, with implications for topological electronics and CMOS-compatible rectification devices.<\/p>\n\n\n\n

Correspondence: mbsn@if.ufrj.br<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Unraveling the (1 \u00d7 1) and (1 \u00d7 2) reconstructed surface structures of SrTiO3<\/sub> (1 1 0) single crystal<\/strong><\/h4>\n\n\n\n
Applied Surface Science, 721, 1, 165401 (2026)<\/strong><\/h6>\n\n\n\n

Alexandre Pancotti, Jenifer J. Silva, Mayron S. Castro, Abner de Siervo, Richard Landers, Pedro A.P. Nascente<\/p>\n\n\n\n

This work, with participation of Prof. Abner de Siervo (UNICAMP), clarifies the atomic structure of (1\u00d71) and (1\u00d72) reconstructions on the polar SrTiO\u2083(110) surface. Combining XPS, LEED, XPD, and MSCD simulations optimized via genetic algorithms, the authors determine that the (1\u00d72) reconstruction consists of a coexistence of ~60% TiO\u2084\u2074\u207a and ~40% O\u2082\u2074\u207b terminations on a (1\u00d71) base. It is provided provide quantitative, element-selective structural determination of a complex polar oxide surface, crucial for interface engineering and controlled epitaxial growth in oxide heterostructures.<\/p>\n\n\n\n

Correspondence: asiervo@ifi.unicamp.br<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Metallicity-driven polar transitions in topological epilayers<\/strong><\/strong><\/h4>\n\n\n\n
Communications Physics, 8, 419 (2025)<\/strong><\/h6>\n\n\n\n

Eduardo D. Stefanato, Nicolas M. Kawahala, Bianca A. Kawata, Paulo H. O. Rappl, Eduardo Abramof & Felix G. G. Hernandez<\/p>\n\n\n\n

This study, with participation of Prof. Felix G. G. Hernandez (USP), explores Bi-doped Pb\u2080.\u2085Sn\u2080.\u2085Te topological epilayers using terahertz time-domain spectroscopy. The authors show that carrier concentration and type can be tuned non-monotonically via Bi doping, enabling control of the ferroelectric transition temperature (Tc = 65\u201395 K). Soft transverse optical phonon behavior reflects metallicity-dependent polar order. It demonstrate simultaneous control of ferroelectric and topological properties through carrier engineering, establishing a tunable platform for polar topological metals.<\/p>\n\n\n\n

Correspondence: felixggh@if.usp.br<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Disorder-induced damping of spin excitations in Cr-doped BaFe2<\/sub>As2<\/sub><\/strong><\/h4>\n\n\n\n
Physical Review Research, 8, L012028 (2026)<\/strong><\/h6>\n\n\n\n

Marli R. Cantarino, Rafael M. P. Teixeira, K. R. Pakuszewski, Wagner R. da Silva Neto, Juliana G. de Abrantes, Mirian Garcia-Fernandez, P. G. Pagliuso, C. Adriano, Claude Monney, Thorsten Schmitt, Eric C. Andrade and Fernando A. Garcia<\/p>\n\n\n\n

This study, with participation of Prof. Pascoal G. Pagliuso (UNICAMP), Eric C. Andrade (USP) and Fernando A. Garcia (USP), investigates how substitutional disorder affects magnetic excitations in the Hund’s metal Ba(Fe\u2081\u208b\u2093Cr\u2093)\u2082As\u2082. Using high-resolution RIXS, ARPES, and theoretical modeling, the authors show that Cr doping introduces local magnetic moments that strongly interact with Fe-derived spin excitations. Magnons progressively soften and broaden with increasing Cr content, becoming overdamped at x = 0.085. A localized spin model incorporating disorder successfully reproduces the experimental trends. Complementary ARPES measurements reveal enhanced electronic localization and suppression of nematic band splitting. The work demonstrates that disorder, rather than carrier doping, may dominate magnetic excitation dynamics in Hund’s metals, providing key insight into the interplay between charge localization and spin fluctuations in iron-based systems.<\/p>\n\n\n\n

Correspondence: fgarcia@if.usp.br<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

Highlights Unveiling the structure\u2013magnetism interplay in the ferrimagnetic pyrochlore Gd2CrSbO7 with significant cryo\u2013magnetocaloric performance Communications Materials, 7, 6 (2026) R. S. Silva Jr, J. E. Rodrigues, C. Santos, Ch Sahle, F. Serrano-S\u00e1nchez, H. L. Andersen, J. Gainza, A. Skorynina, N. Biskup, N. M. Nemes, E C. Passamani, J. L. Mart\u00ednez, N. S. Ferreira & J….<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"iawp_total_views":21,"footnotes":""},"class_list":["post-34","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/pages\/34","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/comments?post=34"}],"version-history":[{"count":6,"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/pages\/34\/revisions"}],"predecessor-version":[{"id":59,"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/pages\/34\/revisions\/59"}],"wp:attachment":[{"href":"https:\/\/www.ufrgs.br\/newinctmqa\/wp-json\/wp\/v2\/media?parent=34"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}