  The demonstration of a quasi-two-dimensional electron gas (2DEG) and
superconducting properties in LaAlO$_3$/SrTiO$_3$ heterostructures has
stimulated intense research activity in recent ten years. The 2DEG has unique
properties that are promising for applications in all-oxide electronic devices.
The superconductivity in such heterostructures has been observed below 300 mK.
For superconductivity applications it is desirable to have more wide
temperature of the existence range and the ability to control superconductivity
properties by external stimulus. Based on first-principles calculations and
theoretical consideration we show that all-oxide heterostructures incorporating
ferroelectric constituent, such as BaTiO$_3$/La$_2$CuO$_4$, allow creating
2DEG. We predict a possibility of a high temperature guasi-two-dimensional
superconductivity state. This state could be switchable between superconducting
and conducting states by ferroelectric polarization reversal. We also discuss
that such structures must be more simple for preparation. The proposed concept
of ferroelectrically controlled interface superconductivity offers the
possibility to design novel electronic devices.
