Gaggl, T.; Misawa, R.; Kriener, M.; Tanaka, Y.; Yamada, R.; Hirschberger, M. Bulk superconductivity in the kagome metal YRu3B2 Journal Article Phys. Scr. 101, 055912 (2026). @article{gaggl_bulk_2026,
title = {Bulk superconductivity in the kagome metal YRu_{3}B_{2}},
author = {T. Gaggl and R. Misawa and M. Kriener and Y. Tanaka and R. Yamada and M. Hirschberger},
url = {https://doi.org/10.1088/1402-4896/ae3c65},
doi = {10.1088/1402-4896/ae3c65},
year = {2026},
date = {2026-02-05},
urldate = {2026-02-01},
journal = {Phys. Scr.},
volume = {101},
number = {5},
pages = {055912},
abstract = {Materials with a kagome lattice have been heavily studied for their exotic electronic band structure, geometrical frustration, high-temperature charge-order transitions, and unconventional electron-phonon coupling. In LaRu3Si2, it was proposed that electronic flat bands conspire with the characteristic phonon spectrum of the kagome lattice to drive enhanced superconductivity at Tc = 6.8 K. Here, we report bulk superconductivity in the structural analogue YRu3B2, which hosts a pristine kagome lattice. We observe a superconducting transition at Tc = 0.7 K through magnetization, resistivity, and heat-capacity measurements in this novel kagome metal.},
keywords = {B5},
pubstate = {published},
tppubtype = {article}
}
Materials with a kagome lattice have been heavily studied for their exotic electronic band structure, geometrical frustration, high-temperature charge-order transitions, and unconventional electron-phonon coupling. In LaRu3Si2, it was proposed that electronic flat bands conspire with the characteristic phonon spectrum of the kagome lattice to drive enhanced superconductivity at Tc = 6.8 K. Here, we report bulk superconductivity in the structural analogue YRu3B2, which hosts a pristine kagome lattice. We observe a superconducting transition at Tc = 0.7 K through magnetization, resistivity, and heat-capacity measurements in this novel kagome metal. |
Yamada, R.; Kurebayashi, D.; Fujishiro, Y.; Okumura, S.; Nakamura, D.; Yasin, F. S.; Nakajima, T.; Yokouchi, T.; Kikkawa, A.; Taguchi, Y.; Tokura, Y.; Tretiakov, O. A.; Hirschberger, M. Emergent electric field induced by dissipative sliding dynamics of domain walls in a Weyl magnet Journal Article Nat. Phys. 22, 239–244 (2026). @article{yamada_emergent_2026,
title = {Emergent electric field induced by dissipative sliding dynamics of domain walls in a Weyl magnet},
author = {R. Yamada and D. Kurebayashi and Y. Fujishiro and S. Okumura and D. Nakamura and F. S. Yasin and T. Nakajima and T. Yokouchi and A. Kikkawa and Y. Taguchi and Y. Tokura and O. A. Tretiakov and M. Hirschberger},
url = {https://doi.org/10.1038/s41567-025-03124-z},
doi = {10.1038/s41567-025-03124-z},
year = {2026},
date = {2026-01-15},
urldate = {2026-01-01},
journal = {Nat. Phys.},
volume = {22},
number = {2},
pages = {239–244},
abstract = {The dynamic motion of topological defects in magnets induces an emergent electric field, as exemplified by the continuous flow of skyrmion vortices. However, the electrodynamics underlying this emergent field remains poorly understood. In this context, magnetic domain walls—one-dimensional topological defects with two collective modes, sliding and spin-tilt—offer a promising platform for exploration. Here we demonstrate that the dissipative motion of domain walls under oscillatory current excitation generates an emergent electric field. We image domain patterns and quantify the domain-wall length under applied magnetic fields in mesoscopic devices based on the magnetic Weyl semimetal NdAlSi. These devices exhibit exceptionally strong domain-wall scattering and a pronounced emergent electric field, as observed in the imaginary component of the complex impedance. Spin dynamics simulations reveal that domain-wall sliding dominates over spin-tilting, in which the phase delay of the domain-wall motion with respect to the driving force impacts the emergent electric field. Our findings establish domain-wall dynamics as a platform for studying emergent electromagnetic fields and motivate further investigations of the coupled motion of magnetic solitons and conduction electrons.},
keywords = {B5},
pubstate = {published},
tppubtype = {article}
}
The dynamic motion of topological defects in magnets induces an emergent electric field, as exemplified by the continuous flow of skyrmion vortices. However, the electrodynamics underlying this emergent field remains poorly understood. In this context, magnetic domain walls—one-dimensional topological defects with two collective modes, sliding and spin-tilt—offer a promising platform for exploration. Here we demonstrate that the dissipative motion of domain walls under oscillatory current excitation generates an emergent electric field. We image domain patterns and quantify the domain-wall length under applied magnetic fields in mesoscopic devices based on the magnetic Weyl semimetal NdAlSi. These devices exhibit exceptionally strong domain-wall scattering and a pronounced emergent electric field, as observed in the imaginary component of the complex impedance. Spin dynamics simulations reveal that domain-wall sliding dominates over spin-tilting, in which the phase delay of the domain-wall motion with respect to the driving force impacts the emergent electric field. Our findings establish domain-wall dynamics as a platform for studying emergent electromagnetic fields and motivate further investigations of the coupled motion of magnetic solitons and conduction electrons. |
Song, W.; Liu, G.; Deng, H.; Yang, T.; Li, Y.; Yan, X. -Y.; Liao, R.; Wang, Q.; Xu, J.; Yan, C.; Zhao, Y.; Qin, H.; Wang, D.; Jing, W.; Shen, D.; Nakayama, K.; Sato, T.; Setty, C.; Wu, D.; Song, B.; Ying, T.; Tian, Z.; Sakai, A.; Nakatsuji, S.; Kumar, H.; Kuntscher, C. A.; Wang, Z.; Xue, Q. -K.; Yin, J. -X. Many-body electronic structure in the pyrochlore superconductor CsBi2 and spin-liquid candidate Pr2Ir2O7 Journal Article Phys. Rev. B 112, 245131 (2025). @article{song_many-body_2025,
title = {Many-body electronic structure in the pyrochlore superconductor CsBi_{2} and spin-liquid candidate Pr_{2}Ir_{2}O_{7}},
author = {W. Song and G. Liu and H. Deng and T. Yang and Y. Li and X. -Y. Yan and R. Liao and Q. Wang and J. Xu and C. Yan and Y. Zhao and H. Qin and D. Wang and W. Jing and D. Shen and K. Nakayama and T. Sato and C. Setty and D. Wu and B. Song and T. Ying and Z. Tian and A. Sakai and S. Nakatsuji and H. Kumar and C. A. Kuntscher and Z. Wang and Q. -K. Xue and J. -X. Yin},
url = {https://link.aps.org/doi/10.1103/6jq5-fgxl},
doi = {10.1103/6jq5-fgxl},
year = {2025},
date = {2025-12-12},
urldate = {2025-12-12},
journal = {Phys. Rev. B},
volume = {112},
number = {24},
pages = {245131},
abstract = {The pyrochlore lattice materials can exhibit geometrical frustration, while the related many-body electronic states remain elusive. In this work, we performed scanning tunneling microscopy measurements on the pyrochlore superconductor CsBi2 and spin liquid Pr2Ir2O7 at 0.3 K. For the first time, we obtained atomically resolved images of their (111) surfaces, revealing a hexagonal lattice or a kagome lattice. Tunneling spectroscopy in CsBi2 reveals a nearly fully opened superconductivity gap. The ratio of 2Δ/𝑘_𝐵𝑇_C=4.7 suggests relatively strong coupling superconductivity, as compared with that in kagome superconductors 𝐴V3Sb5 (𝐴 = K, Rb, Cs). In contrast to the previous study categorizing CsBi2 as a type-I superconductor, the applied magnetic field induces a hexagonal vortex lattice in which each vortex core exhibits an intriguing threefold symmetry state. In Pr2Ir2O7, we observed a spatially homogeneous Kondo-lattice resonance, which is compared with that in the kagome Kondo-lattice material CsCr6Sb6. We further discover that the Kondo resonance exhibits a spatial modulation with threefold symmetry, and the applied magnetic field induces a Zeeman splitting of the Kondo resonance with intriguing atomic site dependence. We discuss the relations of these many-body electronic phenomena with the pyrochlore lattice geometry and its charge or spin frustration. Our systematic observations offer atomic-scale insights into the many-body electronic structures of the geometrically frustrated pyrochlore superconductors and spin liquids.},
keywords = {A1},
pubstate = {published},
tppubtype = {article}
}
The pyrochlore lattice materials can exhibit geometrical frustration, while the related many-body electronic states remain elusive. In this work, we performed scanning tunneling microscopy measurements on the pyrochlore superconductor CsBi2 and spin liquid Pr2Ir2O7 at 0.3 K. For the first time, we obtained atomically resolved images of their (111) surfaces, revealing a hexagonal lattice or a kagome lattice. Tunneling spectroscopy in CsBi2 reveals a nearly fully opened superconductivity gap. The ratio of 2Δ/𝑘_𝐵𝑇_C=4.7 suggests relatively strong coupling superconductivity, as compared with that in kagome superconductors 𝐴V3Sb5 (𝐴 = K, Rb, Cs). In contrast to the previous study categorizing CsBi2 as a type-I superconductor, the applied magnetic field induces a hexagonal vortex lattice in which each vortex core exhibits an intriguing threefold symmetry state. In Pr2Ir2O7, we observed a spatially homogeneous Kondo-lattice resonance, which is compared with that in the kagome Kondo-lattice material CsCr6Sb6. We further discover that the Kondo resonance exhibits a spatial modulation with threefold symmetry, and the applied magnetic field induces a Zeeman splitting of the Kondo resonance with intriguing atomic site dependence. We discuss the relations of these many-body electronic phenomena with the pyrochlore lattice geometry and its charge or spin frustration. Our systematic observations offer atomic-scale insights into the many-body electronic structures of the geometrically frustrated pyrochlore superconductors and spin liquids. |
