Electronic structure, magnetic and transport properties of antiferromagnetic Weyl semimetal GdAlSi

Antu Laha; Asish K. Kundu; Niraj Aryal; Emil S. Bozin; Juntao Yao; Sarah Paone; Anil Rajapitamahuni; Elio Vescovo; Tonica Valla; Milinda Abeykoon; Ran Jing; Weiguo Yin; Abhay N. Pasupathy; Mengkun Liu; Qiang Li

arXiv · 2312.14415

Electronic structure, magnetic and transport properties of antiferromagnetic Weyl semimetal GdAlSi

Antu Laha·Asish K. Kundu·Niraj Aryal·Emil S. Bozin·Juntao Yao·Sarah Paone·Anil Rajapitamahuni·Elio Vescovo·Tonica Valla·Milinda Abeykoon·Ran Jing·Weiguo Yin·Abhay N. Pasupathy·Mengkun Liu·Qiang Li

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Abstract

We report the topological electronic structure, magnetic, and magnetotransport properties of a noncentrosymmetric compound GdAlSi. Magnetic susceptibility shows an antiferromagnetic transition at $T_\mathrm{N}$ = 32 K. In-plane isothermal magnetization exhibits an unusual hysteresis behavior at higher magnetic field, rather than near zero field. Moreover, the hysteresis behavior is asymmetric under positive and negative magnetic fields. First-principles calculations were performed on various magnetic configurations, revealing that the antiferromagnetic state is the ground state, and the spiral antiferromagnetic state is a close competing state. The calculations also reveal that GdAlSi hosts multiple Weyl points near the Fermi energy. The band structure measured by angle-resolved photoemission spectroscopy (ARPES) shows relatively good agreement with the theory, with the possibility of Weyl nodes slightly above the Fermi energy. Within the magnetic ordered state, we observe an exceptionally large anomalous Hall conductivity (AHC) of ~ 1310 $\Omega^{-1}$cm$^{-1}$ at 2 K. Interestingly, the anomalous Hall effect persists up to room temperature with a significant value of AHC (~ 155 $\Omega^{-1}$cm$^{-1}$). Our analysis indicates that the large AHC originates from the Berry curvature associated with the multiple pairs of Weyl points near Fermi energy.

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Antu Laha, Asish K. Kundu, Niraj Aryal, Emil S. Bozin, Juntao Yao, Sarah Paone, Anil Rajapitamahuni, Elio Vescovo, Tonica Valla, Milinda Abeykoon, Ran Jing, Weiguo Yin, Abhay N. Pasupathy, Mengkun Liu, Qiang Li. 2023-12-22. Electronic structure, magnetic and transport properties of antiferromagnetic Weyl semimetal GdAlSi. https://arxiv.org/abs/2312.14415

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