Ubiquitous stripe phase and enhanced electron pairing in the interfacial high- <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>T</mml:mi><mml:mi>c</mml:mi></mml:msub></mml:math> superconductor <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>FeSe</mml:mi><mml:mtext>/</mml:mtext><mml:msub><mml:mi>BaTiO</mml:mi><mml:mn>3</mml:mn></mml:msub></mml:math>

Monolayer FeSe grown on ${\mathrm{SrTiO}}_{3}$ provides a playground for high-${T}_{c}$ superconductivity. Authors of recent study have shown the importance stripy instability superconductivity enhancement in FeSe/${\mathrm{SrTiO}}_{3}$. However, it is still under debate whether such stripe phase ubiquitously bound to interfacial Here, we report molecular beam epitaxy growth and low-temperature scanning tunneling microscopy films $\mathrm{BaTi}{\mathrm{O}}_{3}(001)$. We find that more prominent $\mathrm{s}/\mathrm{BaTi}{\mathrm{O}}_{3}$. Long-range stripes exist bilayer triple-layer at 4 K even persist up 77 case FeSe, with enlarged superconducting gaps upon alkali-metal deposition. The results point out an intimate correlation between phase.