Nanopatterning of weak links in superconducting oxide interfaces
Artikel i vetenskaplig tidskrift, 2021

The interface between two wide band-gap insulators, LaAlO3 and SrTiO3 (LAO/STO), hosts a quasi-two-dimensional electron gas (q2DEG), two-dimensional superconductivity, ferromagnetism, and giant Rashba spin-orbit coupling. The co-existence of two-dimensional superconductivity with gate-tunable spin-orbit coupling and multiband occupation is of particular interest for the realization of unconventional superconducting pairing. To investigate the symmetry of the superconducting order parameter, phase sensitive measurements of the Josephson effect are required. We describe an approach for the fabrication of artificial superconducting weak links at the LAO/STO interface using direct high-resolution electron beam lithography and low-energy argon ion beam irradiation. The method does not require lift-off steps or sacrificial layers. Therefore, resolution is only limited by the electron beam lithography and pattern transfer. We have realized superconducting weak links with a barrier thickness of 30–100 nm. The barrier transparency of the weak links can be controlled by the irradiation dose and further tuned by a gate voltage. Our results open up new possibilities for the realization of quantum devices in oxide interfaces.

Nanopatterned materials

Top-down lithography

Laalo /SrTiO interface 3 3

Two-dimensional superconductivity

Författare

Gyanendra Singh

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

E. Lesne

TU Delft

Dag Winkler

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Tord Claeson

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Thilo Bauch

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Floriana Lombardi

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Andrea D. Caviglia

TU Delft

Alexei Kalaboukhov

Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik

Nanomaterials

20794991 (eISSN)

Vol. 11 2 1-11 398

Ämneskategorier

Atom- och molekylfysik och optik

Annan fysik

Den kondenserade materiens fysik

DOI

10.3390/nano11020398

PubMed

33557305

Mer information

Senast uppdaterat

2021-03-04