Investigations Of Chaos In The Josephson Junction Arrays

Josephson junction is a superconducting weak link and has found wide usage such as metrology, medicine, biology, communication technology, quantum computing and so on. Typical values of power output for single Josephson junction are in the nanowatt range, which is far too small for applications, so Josephson junction arrays (JJAs) have been studying to increase power output. Recently, both theoretical and experimental studies on the JJAs have become forward problems in the chaotic field, and the investigation of the chaos in JJA became one of hot spots in nonlinear physics and chaos of solid.This thesis studies the various dynamical behaviors of the arrays made up of a two and three resistive-capacitive-inductive-shunted Josephson junctions (RCLSJJs) including hyperchaotic, chaotic and periodic behaviors, the route to chaos and controlling the hyperchaos in this system. This thesis presents the following results:1. The arrays can be in the hyperchaotic states and yield the better chaotic signals at this time.2. The arrays enter into the chaotic (or hyperchaotic) states through double-periodic bifurcation or intermittency route.3. The arrays can be in a new periodic state, quasi-anti-periodic state and the array made up of three RCLSJJs will divide into two clusters at some periodic regions.4. The hyperchaos and chaos in the arrays can be controlled by changing dc-bias current and applying ac-bias current.