تقرير
Anisotropic magnetism and electronic structure of trigonal EuAl$_2$Ge$_2$ single crystals
| العنوان: | Anisotropic magnetism and electronic structure of trigonal EuAl$_2$Ge$_2$ single crystals |
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| المؤلفون: | Pakhira, Santanu, Kundu, Asish K., Islam, Farhan, Tanatar, M. A., Roy, Tufan, Heitmann, Thomas, Yilmaz, T., Vescovo, E., Tsujikawa, Masahito, Shirai, Masafumi, Prozorov, R., Vaknin, David, Johnston, D. C. |
| المصدر: | Phys. Rev. B 107, 134439 (2023); 16 pages |
| سنة النشر: | 2023 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Strongly Correlated Electrons |
| الوصف: | The magnetic and electronic properties of the layered Zintl-phase compound EuAl$_2$Ge$_2$ crystallizing in the trigonal CaAl$_2$Si$_2$-type structure are reported. Our neutron-diffraction measurements show that EuAl$_2$Ge$_2$ undergoes A-type antiferromagnetic (AFM) ordering below $T_{\rm N} = 27.5(5)$~K, with the Eu moments (Eu$^{2+}$, $S = 7/2$) aligned ferromagnetically in the $ab$ plane. The $H = 0$ magnetic structure consists of trigonal AFM domains associated with $ab$-plane magnetic anisotropy and a field-induced reorientation of the Eu spins in the domains is evident at $T = 2$~K below the critical field $H_{c1} = 2.5(1)$ kOe. Electrical resistivity and ARPES measurements show that EuAl$_2$Ge$_2$ is metallic both above and below $T_{\rm N}$. In the AFM phase, we directly observe folded bands in ARPES due to the doubling of the magnetic unit cell along the $c$ axis with an enhancement of quasiparticle weight due to the complex change in the coupling between the magnetic moments and itinerant electrons on cooling below $T_{\rm N}$. The observed electronic structure is well reproduced by first-principle calculations, which also predict the presence of nontrivial electronic states near the Fermi level in the AFM phase with $Z_2$ topological numbers 1;(000). Comment: 16 pages, 13 captioned figures, 53 references Updated several affiliations |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1103/PhysRevB.107.134439 |
| URL الوصول: | http://arxiv.org/abs/2301.09613 |
| رقم الأكسشن: | edsarx.2301.09613 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1103/PhysRevB.107.134439 |
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