The Hardy estimates in $\mathbb R^n$ and absence of positive eigenvalues for Schrodinger operators with complex potentials

Using the following estimit
$$ \int_{\mathbb R^n}|x|^{2p+2}|\Delta\varphi+\varphi|^2\,dx\geqslant C(p)\int_{\mathbb R^n}|x|^{2p}|\varphi|^2\,dx $$
with $C(p)\to\infty$ as $p\to\infty$, we prove the absence of $L_2$-solution of
$$ \Delta\varphi+v\varphi=\varphi $$
with $|v(x)|\leqslant C(1+|x|)^{-1-\varepsilon}$.