In a Josephson junction (JJ) at zero bias, Cooper pairs are transported between two superconducting contacts via the Andreev bound states (ABSs) formed in the Josephson channel. Extending JJs to multiple superconducting contacts, the ABSs in the Josephson channel can coherently hybridize Cooper pairs among different superconducting electrodes. Biasing three-terminal JJs with antisymmetric voltages, for example, results in a direct current (DC) of Cooper quartet (CQ), which involves a four-fermion entanglement. Here, we report half a flux periodicity in the interference of CQ formed in graphene based multi-terminal (MT) JJs with a magnetic flux loop. We observe that the quartet differential conductance associated with supercurrent exhibits magneto-oscillations associated with a charge of 4
This content will become publicly available on December 22, 2024
Time-reversal symmetry breaking superconductivity between twisted cuprate superconductors
Twisted interfaces between stacked van der Waals (vdW) cuprate crystals present a platform for engineering superconducting order parameters by adjusting stacking angles. Using a cryogenic assembly technique, we construct twisted vdW Josephson junctions (JJs) at atomically sharp interfaces between Bi2Sr2CaCu2O8+
- NSF-PAR ID:
- 10493708
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science
- Volume:
- 382
- Issue:
- 6677
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 1422 to 1427
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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