The thesis presents research work on numerical modeling of a superconducting switching device called nanocryotron (nTron), whose properties could represent a solution for controlling the charge configuration memory module (CCM). The main problem, which we would like to solve, is extremly fast switching between the read and write state of the CCM at very low teperatures (~4K) with electrical pulses of quite high amplitude (~ 500mV). By connecting an nTron made of NbTiN (niobium titanum nitride) in paralell with the CCM we can manipulate its superconducting properties to achive effective switching and current amplification. The properties in question are the critical current denisty and critical temperature. By exceeding them we change the material's state from superconducting to normal. The change causes a voltage drop on the nTron and causes part of the electrical current to flow throug the CCM. In doing so we are switching between its states of high and low electrical resistivity. This circuit creates a memory cell called paralelotron (pTron).
To prove the above mentioned working principle of the nTron we used the COMSOL software, where we simulated the nTron's change from the superconducting state to the normal state. We achieved this by using different values of electrical current until we exceeded the critical current density in the choke and locally changed the state to normal. We didn't notice any heating of the choke, but we had success with changing part of the channel to the normal state. Based on the results of the simulation we expect further simulations to prove the working principle of the pTron.
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