Large Anomalous Nernst Effects at Room Temperature in Fe Pt Thin Films.

Heat current in ferromagnets can generate a transverse electric voltage perpendicular to magnetization, known as anomalous Nernst effect (ANE). ANE originates intrinsically from the combination of large Berry curvature and density of states near the Fermi energy. It shows technical advantages over the conventional longitudinal Seebeck effect in converting waste heat to electricity due to its unique transverse geometry.

Light-Induced Giant Rashba Spin-Orbit Coupling at Superconducting KTaO (110) Heterointerfaces.

The 2D electron system (2DES) at the KTaO surface or heterointerface with 5d orbitals hosts extraordinary physical properties, including a stronger Rashba spin-orbit coupling (RSOC), higher superconducting transition temperature, and potential of topological superconductivity. Herein, a huge enhancement of RSOC under light illumination achieved at a superconducting amorphous-Hf Zr O /KTaO (110) heterointerfaces is reported. The superconducting transition is observed with T = 0.

Scaling and Diabatic Effects in Quantum Annealing with a D-Wave Device.

We discuss quantum annealing of the two-dimensional transverse-field Ising model on a D-Wave device, encoded on L×L lattices with L≤32. Analyzing the residual energy and deviation from maximal magnetization in the final classical state, we find an optimal L dependent annealing rate v for which the two quantities are minimized. The results are well described by a phenomenological model with two powers of v and L-dependent prefactors to describe the competing effects of reduced quantum fluctuations (for which we see evidence of the Kibble-Zurek mechanism) and increasing noise impact when v is lowered.

Anomalous Quantum-Critical Scaling Corrections in Two-Dimensional Antiferromagnets.

We study the Néel-paramagnetic quantum phase transition in two-dimensional dimerized S=1/2 Heisenberg antiferromagnets using finite-size scaling of quantum Monte Carlo data. We resolve the long-standing issue of the role of cubic interactions arising in the bond-operator representation when the dimer pattern lacks a certain symmetry. We find nonmonotonic (monotonic) size dependence in the staggered (columnar) dimerized model, where cubic interactions are (are not) present.

Critical Level Crossings and Gapless Spin Liquid in the Square-Lattice Spin-1/2 J_{1}-J_{2} Heisenberg Antiferromagnet.

We use the density matrix renormalization group method to calculate several energy eigenvalues of the frustrated S=1/2 square-lattice J_{1}-J_{2} Heisenberg model on 2L×L cylinders with L≤10. We identify excited-level crossings versus the coupling ratio g=J_{2}/J_{1} and study their drifts with the system size L. The lowest singlet-triplet and singlet-quintuplet crossings converge rapidly (with corrections ∝L^{-2}) to different g values, and we argue that these correspond to ground-state transitions between the Néel antiferromagnet and a gapless spin liquid, at g_{c1}≈0.

Dynamical Signature of Symmetry Fractionalization in Frustrated Magnets.

The nontriviality of quantum spin liquids (QSLs) typically manifests in the nonlocal observables that signify their existence; however, this fact actually casts a shadow on detecting QSLs with experimentally accessible probes. Here, we provide a solution by unbiasedly demonstrating a dynamical signature of anyonic excitations and symmetry fractionalization in QSLs. Employing large-scale quantum Monte Carlo simulation and stochastic analytic continuation, we investigate the extended XXZ model on the kagome lattice, and find out that, across the phase transitions from Z_{2} QSLs to different symmetry breaking phases, spin spectral functions can reveal the presence and condensation of emergent anyonic spinon and vison excitations, in particular, the translational symmetry fractionalization of the latter, which can be served as the dynamical signature of the seemingly ephemeral QSLs in spectroscopic techniques such as inelastic neutron or resonance (inelastic) x-ray scatterings.

Quantum Spin Liquid with Even Ising Gauge Field Structure on Kagome Lattice.

Employing large-scale quantum Monte Carlo simulations, we study the extended XXZ model on the kagome lattice. A Z_{2} quantum spin liquid phase with effective even Ising gauge field structure emerges from the delicate balance among three symmetry-breaking phases including stripe solid, staggered solid, and ferromagnet. This Z_{2} spin liquid is stabilized by an extended interaction related to the Rokhsar-Kivelson potential in the quantum dimer model limit.