Let an ellipse \( E:\ \dfrac{x^{2}}{a^{2}}+\dfrac{y^{2}}{b^{2}}=1,\ a^{2}>b^{2} \), passes through \( \left(\dfrac{\sqrt{3}}{2},1\right) \) and has eccentricity \( \dfrac{1}{\sqrt{3}} \). If a circle, centered at focus \( F(\alpha,0),\ \alpha>0 \) of \( E \) and radius \( \dfrac{2}{\sqrt{3}} \) intersects \( E \) at two points \( P \) and \( Q \), then \( PQ^{2} \) is equal to: