# Orbital Selectivity and Magnetic Ordering in Fe intercalated Dirac Semimetal Bi$_2$Se$_3$

## TL;DR

This study explores how iron intercalation in Bi$_2$Se$_3$ modifies its electronic structure, induces ferromagnetism, and causes an orbital-selective metal-insulator transition, revealing new magnetic and transport phenomena.

## Contribution

It provides first-principles insights into the effects of Fe intercalation on the magnetic and electronic properties of Bi$_2$Se$_3$, including orbital selectivity and phase transitions.

## Key findings

- Fe intercalation induces ferromagnetism in Bi$_2$Se$_3$
- Modification of the Dirac cone due to Fe intercalation
- Orbital-selective metal-insulator transition in Fe 3d orbitals

## Abstract

In this paper we investigate the intercalation effects of Iron (Fe) in the van der Waals gap of Bi$_2$Se$_3$ on the magnetic and transport properties using first-principles band structure estimations combined using dynamical mean-field theory. Inclusion of electronic correlations and spin-orbit coupling effects are found to result in the emergence of ferromagnetic properties in an intercalated Bi$_2$Se$_3$. Further the Dirac cone in the band structure of Bismuth Selenide is modified via Fe intercalation at moderate densities. Accompanied by novel structural effects, the onset of an orbital selective metal insulator transition in the Fe 3$d$ orbitals brings about a magnetic phase transition in the Fe intercalated Bi$_2$Se$_3$. Further we have explored the dependency of the inter-orbital electron-electron correlations on the magnetic ordering and the effects of intercalation in establishing new physical properties.