Coexistence of Magnetic Order and Two-dimensional Superconductivity at LaAlO3/SrTiO3 Interfaces
A two dimensional electronic system forms at the interface between the band insulators LaAlO[subscript 3] and SrTiO[subscript 3]. Samples fabricated until now have been found to be either magnetic or superconducting, depending on growth conditions. Combining high-resolution magnetic torque magneto...
Main Authors: | , , , |
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Other Authors: | |
Format: | Article |
Language: | en_US |
Published: |
Nature Publishing Group
2012
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Online Access: | http://hdl.handle.net/1721.1/72011 https://orcid.org/0000-0001-5031-1673 |
Summary: | A two dimensional electronic system forms at the interface between the band insulators LaAlO[subscript 3]
and SrTiO[subscript 3]. Samples fabricated until now have been found to be either magnetic or superconducting,
depending on growth conditions. Combining high-resolution magnetic torque magnetometry
and transport measurements, we report here magnetization measurements providing direct
evidence of magnetic ordering of the two-dimensional electron liquid at the interface. The magnetic
ordering exists from well below the superconducting transition to up to 200 K, and is characterized
by an in-plane magnetic moment. Surprisingly, despite the presence of this magnetic ordering, the
interface superconducts below 120 mK. This is unusual because conventional superconductivity
rarely exists in magnetically ordered metals. Our results suggest that there is either phase
separation or coexistence between magnetic and superconducting states. The coexistence scenario
would point to an unconventional superconducting phase as ground state. |
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