Magnetic Ordering in GdAuAl${}_4$Ge${}_2$ and TbAuAl${}_4$Ge${}_2$: layered compounds with triangular lanthanide nets

Abstract

We report the synthesis of the entire $Ln$AuAl${}_4$Ge${}_2$ ($Ln$ = Y, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, and Tm) series and focus on the magnetic properties of GdAuAl${}_4$Ge${}_2$ and TbAuAl${}_4$Ge${}_2$. Temperature and magnetic field dependent magnetization, heat capacity, and electrical resistivity measurements reveal that both compounds exhibit several magnetically ordered states at low temperatures, with evidence for magnetic fluctuations extending into the paramagnetic temperature region. For magnetic fields applied in the $ab$-plane there are several ordered state regions that are associated with metamagnetic phase transitions, consistent with there being multiple nearly degenerate ground states. Despite Gd being an isotropic $S$-state ion and Tb having an anisotropic $J$-state, there are similarities in the phase diagrams for the two compounds, suggesting that factors such as the symmetry of the crystalline lattice, which features well separated triangular planes of lanthanide ions, or the Ruderman-Kittel-Kasuya-Yosida interaction as defined by the Fermi surface topography control the magnetism. We also point out similarities to other centrosymmetric compounds that host skyrmion lattices such as Gd${}_2$PdSi${}_3$, and propose that the $Ln$AuAl${}_4$Ge${}_2$ family of compounds are of interest as reservoirs for complex magnetism and electronic behaviors such as the topological Hall effect.

arXiv comment10 pages, 11 figures

References in corpus (24)

• Skyrmion Lattice in a Chiral Magnet
• Higher-order topological insulators and semimetals on the breathing Kagome and pyrochlore lattices
• Topological Kondo Insulators
• Skyrmion lattice with a giant topological Hall effect in a frustrated triangular-lattice magnet
• Superconducting phases of f-electron compounds
• Multiply periodic states and isolated skyrmions in an anisotropic frustrated magnet
• Topological insulator on the kagome lattice
• Skyrmion phase and competing magnetic orders on a breathing kagome lattice
• Nanometric square skyrmion lattice in a centrosymmetric tetragonal magnet
• Use of frit-disc crucibles for routine and exploratory solution growth of single crystalline samples
• Quantized Anomalous Hall Effects in Skyrmion Crystal
• Antiferromagnetic skyrmion crystals: generation, topological Hall and topological spin Hall effect
• Magnetic anisotropy, first-order-like metamagnetic transitions and large negative magnetoresistance in the single crystal of Gd${}_2$PdSi${}_3$
• First order transition from antiferromagnetism to ferromagnetism in Ce(Fe${}_{0.96}$Al${}_{0.04}{)}_2$
• Observation of a temperature dependent electrical resistance minimum above the magnetic ordering temperature in Gd${}_2$PdSi${}_3$
• Magnetic and transport anomalies in R2RhSi3 (R= Gd, Tb, and Dy), resembling those of an exotic magnetic skyrmion Gd2PdSi3
• Face centered cubic and hexagonal close packed skyrmion crystals in centro-symmetric magnets
• Resistivity Minimum in Highly Frustrated Itinerant Magnets
• Quasiquartet CEF ground state with possible quadrupolar ordering in the tetragonal compound YbRu${}_2$Ge${}_2$
• Hysteretic magnetoresistance and unconventional anomalous Hall effect in the frustrated magnet TmB_4
• Neutron diffraction evidence for kinetic arrest of first-order magneto-structural phase transitions in some functional magnetic materials
• Possible devil's staircase in the Kondo lattice CeSbSe
• Topical Review on Skyrmions and Hall Transport
• Electronic Structure and Magnetism in the Layered Triangular Lattice Compound CeAuAl${}_4$Ge${}_2$

Cited by in corpus (4)

• Magnetization plateau and anisotropic magnetoresistance in the frustrated Kondo-lattice compound Ce3ScBi5
• Magnetic phase diagram and multiple field-induced states in the intermetallic triangular-lattice antiferromagnet NdAuAl${}_4$Ge${}_2$ with Ising-like spins
• Metallic layered materials with magnetic frustration: An ARPES view of the SmAuAl${}_4$Ge${}_2$ and TbAuAl${}_4$Ge${}_2$
• Anisotropic magnetism of polymorphic ErAl3