Periodicity in Al/Ti superconducting single electron transistors

@article{MacLeod2009PeriodicityIA,
  title={Periodicity in Al/Ti superconducting single electron transistors},
  author={Sarah J. MacLeod and S. Kafanov and Jukka P. Pekola},
  journal={Applied Physics Letters},
  year={2009},
  volume={95},
  pages={052503}
}
We present experiments on single Cooper-pair transistors made of two different superconducting materials. We chose Ti and Al to create an energy gap profile such that the island has a higher gap than the leads, thereby acting as a barrier to quasiparticle tunneling. Our transport measurements demonstrate that quasiparticle poisoning is suppressed in all our TiAlTi structures (higher gap for the island) with clear 2e periodicity observed, whereas full quasiparticle poisoning is observed in all… 
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References

SHOWING 1-10 OF 39 REFERENCES
Parity effect in superconducting aluminum single electron transistors with spatial gap profile controlled by film thickness
We propose a novel method for suppression of quasiparticle poisoning in Al Coulomb blockade devices. The method is based on creation of a proper energy gap profile along the device. In contrast to…
Nonequilibrium quasiparticles and 2e periodicity in single-Cooper-pair transistors.
TLDR
A model based on nonequilibrium quasiparticles in the leads explains results, including the observation that even devices with a clean 2e period are "poisoned" by small numbers of these quasIParticles.
Experimental evidence for parity-based 2e periodicity in a superconducting single-electron tunneling transistor.
TLDR
Experimental current-voltage measurements on an Al-Al 2 O 3 -Al single-electron tunneling transistor in the superconducting state are presented, finding that the I-V curve is 2e periodic with respect to the gate-induced charge.
Fabrication of Nb-based superconducting single electron transistor
Parity effect in Al and Nb single electron transistors in a tunable environment
Two different types of Cooper pair transistors, with Al and Nb islands, have been investigated in a tunable electromagnetic environment. The device with an Al island demonstrates gate charge…
Fabrication and measurement of a Nb based superconducting single electron transistor
A new four‐layer resist system was developed to fabricate small capacitance niobium tunnel junctions. Nb/AlOx/Al junctions were used to make a superconducting single electron transistor composed of…
Even-odd asymmetry of a superconductor revealed by the Coulomb blockade of Andreev reflection.
TLDR
The 2e-periodic current peaks are the first observation of the Coulomb blockade of Andreev reflection and are clear evidence that there is a difference in the total energy between the ground states of an even and odd number of electrons on the island.
Even-odd electron number effects in small superconducting islands
Quasiparticle cooling of a single Cooper pair transistor
A superconducting tunnel junction is used to directly extract quasiparticles from one of the leads of a single Cooper pair transistor. The consequent reduction in quasiparticle density causes a lower…
Energy gap measurement of nanostructured aluminium thin films for single Cooper-pair devices
We report measurements of the superconducting gap in Al–Al2O3–Al tunnel junctions as a function of aluminium film thickness. Films of thickness 5, 7, 10 and 30 nm were used to form the small-area…
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