Hidden magnetic frustration by quantum relaxation in anisotropic Nd-langasite
Virginie Simonet, Rafik Ballou, Julien Robert, Benjamin Canals, Françoise Hippert, Pierre Bordet, Pascal Lejay, Peter Fouquet, Jacques Ollivier, Daniel Braithwaite
本文重新研究了Nd $_3$ Ga $_5$ SiO $_{14}$化合物的静态和动态磁性质，该化合物是稀土kagome型晶格的第一个物质化产物。中子散射，磁化和比热测量进行和分析，特别是充分考虑晶体电场对Nd $^{3+}$离子的影响。新的发现之一是，在10 K以下观察到的独特的温度无关的自旋动力学表达单离子量子过程。这将使只有在非常低的温度下才会出现的挫折感引起的合作动力短路。
英文摘要：
The static and dynamic magnetic properties of the Nd$_3$Ga$_5$SiO$_{14}$ compound, which appears as the first materialization of a rare-earth kagome-type lattice, were re-examined, owing to contradictory results in the previous studies. Neutron scattering, magnetization and specific heat measurements were performed and analyzed, in particular by fully taking account of the crystal electric field effects on the Nd$^{3+}$ ions. One of the novel findings is that the peculiar temperature independent spin dynamics observed below 10 K expresses single-ion quantum processes. This would short-circuit the frustration induced cooperative dynamics, which would emerge only at very low temperature.
We study the magnetic properties of CaFeTi$_2$O$_6$ (CFTO) by high-field magnetization and specific heat measurements. While the magnetic susceptibility data yield a vanishingly small Curie-Weiss temperature, the magnetic moments are not fully polarized in magnetic field up to 60 T, which reveals a large spin exchange energy scale. Yet, the system shows no long range magnetic order but a spin-glass-like state below 5.5 K in zero field, indicating strong magnetic frustration in this system. Applying magnetic field gradually suppresses the spin-glass-like state and gives rise to a potential quan…
We report the existence of a phase transition at high temperature in the 3D Kitaev candidate material, $β$-Li$_2$IrO$_3$. We show that the transition is bulk, intrinsic and orders a tiny magnetic moment with a spatially anisotropic saturation moment. We show that even though this transition is global, it does not freeze the local Ir moments, which order at much lower temperatures into an incommensurate state. Rather, the ordered moment has an orbital origin that is coupled to spin correlations, likely of a Kitaev origin. The separate ordering of spin-correlated orbital moments and of local Ir …
We propose utilizing the Cooper pair to induce magnetic frustration in systems of two-dimensional (2D) magnetic adatom lattices on s-wave superconducting surfaces. The competition between singlet electron correlations and the RKKY coupling is shown to lead to a variety of hidden order states that break the point-group symmetry of the 2D adatom lattice at finite temperature. The phase diagram is constructed using a newly developed effective bond theory [M. Schecter et al., Phys. Rev. Lett. 119, 157202 (2017)], and exhibits broad regions of long-range vestigial nematic order.
The unconventional magnetic orderings found in Kitaev spin liquid candidates suggest frustration of spin interactions, and raise a possibility of nearby spin liquid phases. In particular, counter-rotating spiral ordering in three-dimensional (3D) iridates is striking, and understanding the microscopic mechanism of such ordering may provide routes to 3D Kitaev spin liquids. We study a minimal 3D model including Kitaev $K$ and a symmetric off-diagonal bond-dependent $Γ$ interaction on the hyperhoneycomb lattice using exact diagonalization. We first show that a 12-site unitary transformation unve…
Frustration in magnetic interactions can give rise to disordered ground states with subtle and beautiful properties. The spin ices Ho2Ti2O7 and Dy2Ti2O7 exemplify this phenomenon, displaying a classical spin liquid state, with fractionalized magnetic--monopole excitations. Recently there has been great interest in closely-related "quantum spin ice" materials, following the realization that anisotropic exchange interactions could convert spin ice into a massively-entangled, quantum, spin liquid, where magnetic monopoles become the charges of an emergent quantum electrodynamics. Here we show tha…
Discovery of hidden order in the Shastry-Sutherland magnet Nd2Be2GeO7
Songshan Lake Materials Laboratory（松山湖材料实验室）；School of Physics and Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology（华中科技大学物理学院与武汉国家强磁场中心）；Laboratory for Neutron Scattering and Imaging DMC, PSI（瑞士保罗谢尔研究所中子散射与成像实验室DMC）；PSI Center for Neutron and Muon Sciences（瑞士保罗谢尔研究所中子与缪子科学中心）；ISIS Neutron and Muon Source, Rutherford Appleton Laboratory（卢瑟福阿普尔顿实验室ISIS中子与缪子源）；Material Science and Technology Division, Oak Ridge National Laboratory（橡树岭国家实验室物质科学与技术部）；School of Physical Sciences, Great Bay University（大湾区大学物理科学学院）；Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）
Cascade of magnetic-field-induced quantum spin states in a spin-1 honeycomb magnet
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China（合肥微尺度物质科学国家研究中心，中国科学技术大学）；School of Physics, Nanjing University of Science and Technology（南京理工大学物理学院）；National Laboratory of Solid State Microstructures and School of Physics, Nanjing University（南京大学固体微结构物理国家重点实验室和物理学院）；School of Physics, Hefei University of Technology（合肥工业大学物理学院）；Department of Physics, University of Science and Technology of China（中国科学技术大学物理系）；Collaborative Innovation Center of Advanced Microstructures and Jiangsu Physical Science Research Center, Nanjing University（南京大学先进微结构协同创新中心与江苏省物理科学研究院）；Hefei National Laboratory, University of Science and Technology of China（合肥国家实验室，中国科学技术大学）
Tunable bifurcation of magnetic anisotropy and bi-oriented antiferromagnetic order in kagome metal GdTi3Bi4
Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学）；Department of Physics and State Key Laboratory of Surface Physics, Fudan University（复旦大学）
Out-of-equilibrium investigation of strongly correlated materials deciphers the hidden equilibrium properties. Herein, we have investigated the out-of-equilibrium magnetic properties of polycrystalline Dy2Ti2O7 and Ho2Ti2O7 spin ices. The experimental results show the emergence of magnetic field-induced anomalous hysteresis observed only in temperature/magnetic field-dependent ac susceptibility measurements. The observed memory effect (anomalous thermomagnetic hysteresis) strongly depends on the driving thermal and non-thermal variables. Contrary, in the absence of the magnetic field, dipolar …
