Sist tunneling theory

Alessandro Sist

Arthur Cohn, Mario Rabinowitz

Readout Gates, Perng-Fei Yuh, Oleg A. Mukhanov

Experimental superconducting shift registers con- sisting of on-chip clock generators, clock regeneration and dis- tribution circuits, shift register elements, and readout circuits are designed using rapid single flux quantum logic / memory (RSFQ) gates. A 7-b shift register has been tested to 12 GHz and a 17-b to 21 GHz using external triggering clocks with relative delay measurements. Testing with internal clocks generated from Josephson oscillations shows a potential high-speed opera- tion of 45 GHz for the 7-b and 30 GHz for the 17-b shift registers. Two types of magnetically coupled readout gates are discussed. The chips are fabricated using a Nb/AIO,/Nb Josephson-junction process at a critical-current density of 1000 A / cm2. The power dissipation per bit is 3 p.W.

Ángel S. Sanz, Salvador Miret-Artés

Brita Vesterås

NORSK: \nMasteroppgaven tar for seg noen av de siste foreslåtte protokollene for nøkkel-utveksling.\nEttersom de er så nye, har de ikke gjennomgått en detaljert analyse, og kan derfor inneholde\nsikkerhetshull. Sikkerhet i protokollene er viktig, ettersom de er ansvarlig for\nintegriteten og konfidensialiteten til all kommunikasjon fra det øyeblikket de tas i bruk.\nFor å unngå problemer er det viktig å finne den protokollen som har best sikkerhet.\nNye protokoller blir foreslått for å prøve å tilfredsstille kravene, men det er ikke noe bevis\nfor at de har klart det.\nDenne masteroppgaven vil analysere noen av disse nye protokollene og prøve å avdekke\nderes svakheter. Vi prøver også å forbedre de protokollene der vi finner svakheter.

Arnon Ben levy, Amir Hen, Merav Kahn +5 more

The problem of tunneling ionization and the associated questions of how long it takes for an electron to tunnel through the barrier, and what the tunneling rate has fascinated scientists for almost a century. In strong field physics, tunnel ionization plays an important role, and accurate knowledge of the time-dependent tunnel rate is of paramount importance. The Keldysh theory and other more advanced related theories are often used, but their accuracy is still controversial. In previous work, we suggested using a curved waveguide as a quantum simulator to simulate the tunnel ionization process. Here we implemented for the first time such a curved waveguide and observed the simulated tunneling ionization process. We compare our results with the theory.