Stable He${}^{-}$ can exist in a strong magnetic field

Abstract

The existence of bound states of the system $(\al,e,e,e)$ in a magnetic field $B$ is studied using the variational method. It is shown that for $B\gtrsim 0.13a.u.$ this system gets bound with total energy below the one of the $(\al,e,e)$ system. It manifests the existence of the stable He${}^{-}$ atomic ion. Its ground state is a spin-doublet ${}^2(-1{)}^{+}$ at $0.74a.u.\gtrsim B\gtrsim 0.13a.u.$ and it becomes a spin-quartet ${}^4(-3{)}^{+}$ for larger magnetic fields. For $0.8a.u.\gtrsim B\gtrsim 0.7a.u.$ the He${}^{-}$ ion has two (stable) bound states ${}^2(-1{)}^{+}$ and ${}^4(-3{)}^{+}$.

4 pages, 1 figure, 2 tables, one reference added, typos corrected, small modifications done, to be published at Phys Rev Letters

Cited by in corpus (1)

• The He${}_2^{+}$ molecular ion and the He${}^{-}$ atomic ion in strong magnetic fields