5 papers
Non-Hermiticity-induced chirality imbalance of Weyl Landau levels
Sachin Vaidya, Alaa Bayazeed, André Grossi Fonseca +3
Weyl semimetals obey a global chirality constraint: the net chiral topological charge and any associated chiral spectral flow must vanish, as required by the Nielsen-Ninomiya theor…
Exceptional topology on nonorientable manifolds
J. Lukas K. König, Kang Yang, André Grossi Fonseca +3
We classify gapped phases and characteristic nodal points of non-Hermitian band structures on two-dimensional nonorientable parameter spaces. Such spaces arise in a wide range of p…
Gradient-based search of quantum phases: discovering unconventional fractional Chern insulators
André Grossi Fonseca, Eric Wang, Sachin Vaidya +3
The discovery and understanding of new quantum phases has time and again transformed both fundamental physics and technology, yet progress often relies on slow, intuition-based the…
Refining Heuristic Predictors of Fractional Chern Insulators using Machine Learning
Oriol Mayné i Comas, Oriol Mayné i Comas, André Grossi Fonseca +4
We develop an interpretable, data-driven framework to quantify how single-particle band geometry governs the stability of fractional Chern insulators (FCIs). Using large-scale exac…
Quantized crystalline-electromagnetic responses in insulators
Sachin Vaidya, André Grossi Fonseca, Mark R. Hirsbrunner +2
We introduce new classes of gapped topological phases characterized by quantized crystalline-electromagnetic responses, termed "multipolar Chern insulators". These systems are char…