Electronic and magnetic structures of bilayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mtext>La</mml:mtext> <mml:mn>3</mml:mn> </mml:msub> <mml:msub> <mml:mtext>Ni</mml:mtext> <mml:mn>2</mml:mn> </mml:msub> <mml:msub> <mml:mtext>O</mml:mtext> <mml:mn>7</mml:mn> </mml:msub> </mml:mrow> </mml:math> at ambient pressure
Yuxin Wang, Kun Jiang, Ziqiang Wang, Fu‐Chun Zhang, Jiangping Hu
Abstract
We carry out a systematic study of the electronic and magnetic structure of the ambient-pressure bilayer ${\mathrm{La}}_{3}{\mathrm{Ni}}_{2}{\mathrm{O}}_{7}$. Employing the hybrid exchange-correlation functional, we show that the exchange correlation pushes the bonding ${d}_{{z}^{2}}$ bands below the Fermi level to be fully occupied. The calculated Fermi surfaces and the correlation normalized band structure match well with the experimental findings at ambient pressure. Moreover, the electronic susceptibility calculated for this band structure features nesting-induced peaks near the wave vector $Q=(\ensuremath{\pi}/2,\ensuremath{\pi}/2)$, suggesting a possible density wave instability in agreement with recent experiments. Through a mean-field study and $\text{DFT}+U$ calculation introducing a Hubbard U interaction within conventional density functional theory, we confirm the spin-charge intertwined double-stripe order is the magnetic ground state. Our results provide a faithful description for the low-pressure ${\mathrm{La}}_{3}{\mathrm{Ni}}_{2}{\mathrm{O}}_{7}$ electronic structure.