Consider the self-adjoint operator on $L^{2}(\mathbb{R}^{N})$, 

$$H=-\frac{1}{2}(\nabla-iA)^{2}+V,$$
 where $A\in C^{\infty}(\mathbb{R}^{N}, \mathbb{R}^{N} )$, $V\in C^{\infty}(\mathbb{R}^{N})$, $V\geq 0$ and $V(x)\rightarrow\infty$ as $|x|\rightarrow\infty$. 

Does H have a purely discrete spectrum?