Topological Insulators, Altermagnets, and other Quantum Materials

Surface states of HfTe

_{5}

measured via ARPES and calculated via DFT.

I frequently collaborate with experimental groups to guide and explain their findings across a diverse range of quantum materials.

Recent and Current Projects

Identifying multiple topological gaps and hexagonal warping in the layered topological insulator Bi $_{4}$ Te $_{3}$ .
Studying the role of defects and strain in topological phase transition in quasi-one-dimensional HfTe $_{5}$ .
Elucidating the role of the crystal field in the $g$ -wave altermagnet CoNb $_{4}$ Se $_{8}$ , an intercalated transition metal dichalcogenide.
Developing models to explain Turing pattern formation in rare earth hexagonal manganites.

Nicholas Dale, Omar A. Ashour, Marc Vila, Justin Fox, Resham Regmi, Alexei Fedorov, Alexander Stibor, Nirmal Ghimire, Sinéad M. Griffin (2024). Non-relativistic spin splitting above and below the Fermi level in a *g*-wave altermagnet. arXiv.

Omar A. Ashour, Donald M. Evans, Erik. D. Roede, Per Erik Vullum, Zewu Yan, Edith Bourret, Sverre M. Selbach, Sinéad M. Griffin, Dennis Meier (2024). Investigation of the nanoscale stability of the hexagonal rare earth manganites. In Preparation.

Thais Chagas, Omar A. Ashour, Guilherme Ribeiro, Wendell Silva, Zhenglu Li, Rogério Magalhães-Paniago, Yves Petroff, Steven G. Louie (2022). Multiple Strong Topological Gaps and Hexagonal Warping in Bi

_{4}

_{3}

. Physical Review B.

Na Hyun Jo, Omar A. Ashour, Zhixue Shu, Chris Jozwiak, Aaron Bostwick, Sae Hee Ryu, Kai Sun, Tai Kong, Sinéad M. Griffin, Eli Rotenberg (2024). Effects of strain, defects, and interactions on the topological properties of HfTe

_{5}

. Phys. Rev. B.