ABSTRACT
Topological superconductors (TSCs) have garnered significant research and industry attention in the past two decades. By hosting Majorana bound states which can be used as qubits that are robust against local perturbations, TSCs offer a promising platform toward (nonuniversal) topological quantum computation. However, there has been a scarcity of TSC candidates, and the experimental signatures that identify a TSC are often elusive. In this Perspective, after a short review of the TSC basics and theories, we provide an overview of the TSC materials candidates, including natural compounds and synthetic material systems. We further introduce various experimental techniques to probe TSCs, focusing on how a system is identified as a TSC candidate and why a conclusive answer is often challenging to draw. We conclude by calling for new experimental signatures and stronger computational support to accelerate the search for new TSC candidates.
ABSTRACT
The interplay between magnetism and electronic band topology enriches topological phases and has promising applications. However, the role of topology in magnetic fluctuations has been elusive. Here, we report evidence for topology stabilized magnetism above the magnetic transition temperature in magnetic Weyl semimetal candidate CeAlGe. Electrical transport, thermal transport, resonant elastic X-ray scattering, and dilatometry consistently indicate the presence of locally correlated magnetism within a narrow temperature window well above the thermodynamic magnetic transition temperature. The wavevector of this short-range order is consistent with the nesting condition of topological Weyl nodes, suggesting that it arises from the interaction between magnetic fluctuations and the emergent Weyl fermions. Effective field theory shows that this topology stabilized order is wavevector dependent and can be stabilized when the interband Weyl fermion scattering is dominant. Our work highlights the role of electronic band topology in stabilizing magnetic order even in the classically disordered regime.
ABSTRACT
Column selection and experimental design are recognized to be wear-and-tear processes to obtain a good fingerprinting result with comprehensive two dimensional gas chromatography (GCâ¯×â¯GC). The processes involve a large number of experiments for analysis of each sample due to the optimized conditions depending on the selected column sets. In this study, the analytical solutions of time summation model combined with temperature dependent linear solvation energy relationship (LSER) were derived for constant flow separation in GCâ¯×â¯GC. The derived equations allow calculation of analyte retention time in first and second dimensional separation (1tR and 2tR), under temperature program separation employing any column combination with known LSER database. As a result, optimization software was developed enabling simulation of several hundred thousand GCâ¯×â¯GC results (fingerprints) for separation of each sample. Good correlations between our predicted results and the results obtained with the previously established numerical approach, were obtained with the R2 of 1.000 and 0.998 for simulation of 1tR and 2tR, respectively. The developed approaches were further applied to simulation of 96,000 individual fingerprints in temperature programmed GCâ¯×â¯GC, with the focus on application of 16 column sets including non-ionic liquid and ionic liquid (IL) stationary phases for separation of 678 model compounds. These approaches resulted in the computational time of 1 day compared with 1â¯year provided by the numerical method. Best column sets and experimental conditions (secondary column lengths and temperature programs) could then be extracted according to maximizing number of separated peaks in separation, which represents the quality of each fingerprinting.
