Developing new techniques to design and discover novel quantum materials and architectures poses an exciting frontier in condensed-matter research. In particular, synthesis of additional superconductors, especially those with unusual symmetries of superconducting order parameters and/or exotic pairing mechanisms, opens new doors to future applications in quantum devices. In this seminar, the speaker will present research efforts on atomic-scale growth and engineering of such unconventional superconductors in complex oxide heterostructures, based on two extraordinary examples: SrTiO₃ and nickelates. In the first part, he will elucidate the “polar catastrophe” scenario as the origin of the two-dimensional electron system at the celebrated LaAlO₃/SrTiO₃ interfaces and discuss low-dimensional superconductivity in the related heterostructures.