The superconductivity of SrTiO3 has been enigmatic since its discovery in 1964. Thanks to the conductive-AFM lithography, we systematically examine the superconductivity in LaAlO3/SrTiO3 channels with widths that transition from the 1D to the 2D regime.
The superconducting critical current is independent of the channel width and increases approximately linearly with the number of parallel channels. Signatures of electron pairing outside of the superconducting regime are also found to be independent of the channel width. Collectively, these results indicate that superconductivity exists at the boundary of these channels and is absent within the interior region of the channels. The intrinsic 1D nature of superconductivity at the LaAlO3/SrTiO3 interface imposes strong physical constraints on possible electron pairing mechanisms.
Yun-Yi Pai, Anthony Tylan-Tyler, Patrick Irvin, Jeremy Levy, LaAlO3/SrTiO3: a tale of two magnetisms,
Vol. 2, Ch.12, in Spintronics Handbook, Second Edition: Spin Transport and Magnetism, 2nd ed., CRC Press 2019.
Yun-Yi Pai, Anthony Tylan-Tyler, Patrick Irvin, Jeremy Levy, Physics of SrTiO3-based heterostructures and nanostructures: a review, Rep. Prog. Phys. 81 036503 (2018).
Yun-Yi Pai, Hyungwoo Lee, Jung-Woo Lee, Anil Annadi, Guanglei Cheng, Shicheng Lu, Michelle Tomczyk, Mengchen Huang, Chang-Beom Eom, Patrick Irvin, Jeremy Levy, One-Dimensional Nature of Pairing and Superconductivity at the LaAlO3/SrTiO3 Interface, Phys. Rev. Lett. 120, 147001 (2018).