Ballistic Graphene Josephson Junctions from the Short to the Long Junction Regimes.
نویسندگان
چکیده
We investigate the critical current I_{C} of ballistic Josephson junctions made of encapsulated graphene-boron-nitride heterostructures. We observe a crossover from the short to the long junction regimes as the length of the device increases. In long ballistic junctions, I_{C} is found to scale as ∝exp(-k_{B}T/δE). The extracted energies δE are independent of the carrier density and proportional to the level spacing of the ballistic cavity. As T→0 the critical current of a long (or short) junction saturates at a level determined by the product of δE (or Δ) and the number of the junction's transversal modes.
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ورودعنوان ژورنال:
- Physical review letters
دوره 117 23 شماره
صفحات -
تاریخ انتشار 2016