Positive magnetoconductance in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>SrVO</mml:mi> <mml:mn>3</mml:mn> </mml:msub> </mml:mrow> </mml:math> double quantum wells with a magnetic <mml:math xmlns:mml="http

Controlling Mott insulator states has been a long-standing topic in condensed matter physics. Among various controlling parameters, two-dimensional (2D) confinement in epitaxial heterostructures has been demonstrated to convert the correlated metallic nature of ${\mathrm{SrVO}}_{3}$ into a Mott insulator by reducing the quantum well thickness. Here, we fabricate double quantum well (DQW) structures of ${\mathrm{SrVO}}_{3}$ with a magnetic barrier of ${\mathrm{EuTiO}}_{3}$ to tune the hybridization of wave functions by a magnetic field. A significant positive magnetoconductance is observed for DQWs with barriers thinner than 2 nm, while DQWs with thicker barriers do not show such large positive magnetoconductance, instead behaving as a parallel circuit of two single QWs. The observed positive magnetoconductance is accounted for in terms of enhanced hybridization of V $3d$ orbitals across the ${\mathrm{EuTiO}}_{3}$ barrier under a magnetic field, where the barrier height is reduced by the Zeeman splitting of Ti $3d$ bands in forced ferromagnetic ordering of localized $4f$ electrons on $\mathrm{E}{\mathrm{u}}^{2+}$ sites.