Related papers: Frustration, strain and phase co-existence in the …
The anomalous thermal expansion in a layered 3$d$-5$d$ based triple perovskite iridate Ba$_{3}$CoIr$_{2}$O$_{9}$ is investigated using high resolution synchrotron diffraction. Below the magneto-structural transition at 107\,K, the onset of…
We report a comprehensive investigation of the triple perovskite iridate Ba$_{3}$CoIr$_{2}$O$_{9}$. Stabilizing in the hexagonal $P6_{3}/mmc$ symmetry at room temperature, this system transforms to a monoclinic $C2/c$ symmetry at the…
Experimental and theoretical studies are performed on La3Ir3O11, an iridate hosting a +4.33 fractional valence state for Ir ions and a three-dimensional frustrated structure composed of edge-shared Ir2O10 dimers. These features are expected…
We report on thermodynamic, magnetization, and muon spin relaxation measurements of the strong spin-orbit coupled iridate Ba$_3$IrTi$_2$O$_9$, which constitutes a new frustration motif made up a mixture of edge- and corner-sharing…
Perovskite iridates of 6H hexagonal structure present a plethora of possibilities in terms of the variety of ground states resulting from a competition between spin-orbit coupling (SOC), hopping, noncubic crystal field ($\Delta_{CFE}^{NC}$)…
We present an experimental investigation of the magnetic ground state in Ba$_4$NbIr$_3$O$_{12}$, a fractional valent trimer iridate. X-ray absorption and photoemission spectroscopy show that the Ir valence lies between 3+ and 4+ while Nb is…
We report a comprehensive investigation of the quadruple perovskite Ba$_4$NaRu$_3$O$_{12}$, in which we discover a robust spin-lattice coupled ground state characterized by a long-range antiferromagnetic ordering at $T_N \sim$ 257 K. The…
The hexagonal polymorph of Ba$_3$Tb(BO$_3$)$_3$ contains Tb$^{3+}$ ions on a quasi-2D triangular lattice, resulting in geometric magnetic frustration. Powder samples of Ba$_3$Tb(BO$_3$)$_3$ have been investigated using specific heat, powder…
Here, we report both ac and dc magnetization, thermodynamic and electric properties of hexagonal Ba$_3$NiIr$_2$O$_9$. The Ni$^{2+}$ (spin-1) forms layered triangular-lattice and interacts antiferromagnetically while Ir$^{5+}$ is believed to…
Quantum-disordered magnetic ground states are challenging to identify in three-dimensional (3D) oxides, where strong exchange pathways typically favour long-range magnetic order or spin freezing. The quadruple perovskite…
The subtle interplay between competing degrees of freedom, crystal electric fields, and spin correlations can lead to exotic quantum states in 4f ion-based frustrated triangular lattice antiferromagnets. We present the crystal structure,…
Hybrid transition metal oxides continue to attract attention due to their multiple degrees of freedom ($e.g.$, lattice, charge, spin, and orbital) and versatile properties. Here we investigate the magnetic and electronic properties of the…
We report the structural and magnetic ground state properties of the monoclinic compound barium iridium oxide Ba$_4$Ir$_3$O$_{10}$ using a combination of resonant x-ray scattering, magnetometry, and thermodynamic techniques. Magnetic…
The usual classical behaviour of S = 3/2, B-site ordered double perovskites generally results in simple, commensurate magnetic ground states. In contrast, heat capacity and neutron powder diffraction measurements for the S = 3/2 systems…
Frustrated systems exhibit remarkable properties due to the high degeneracy of their ground states. Stabilised by competing interactions, a rich diversity of typically nanometre-sized phase structures appear in polymer and colloidal…
Magnetic frustration and disorder are key ingredients to prevent the onset of magnetic order. In the disordered hexagonal double perovskite BaTi$_{1/2}$Mn$_{1/2}$O$_{3}$, Mn$^{4+}$ cations, with $S=3/2$ spins, can either form highly…
Based on Kitaev-Heisenberg model with Dzyaloshinskii-Moriya (DM) interactions, we studied nature of possible magnetic phases in frustrated hyperkagome iridate, Na$_4$Ir$_{3}$O$_8$ (Na-438). Using Monte-Carlo simulation, we showed that the…
Geometric frustration is a phenomenon in a lattice system where not all interactions can be satisfied, the simplest example being antiferromagnetically coupled spins on a triangular lattice. Frustrated systems are characterized by their…
Magnetic frustration, the competition among exchange interactions, often leads to novel magnetic ground states with unique physical properties which can hinge on details of interactions that are otherwise difficult to observe. Such states…
Frustration of long-range order via lattice geometries serves to amplify fluctuations of the order parameter and generate unconventional ground states that are highly sensitive to perturbations. Traditionally, this concept of geometric…