This master thesis presents research work on the parallelotron (pTron) memory cell, which, due to its unique properties, offers a solution to the lack of memory technology in cryo-computing, where the energy efficiency requirements are very high. Tantalum disulphide is a layered material that is the active material in the memory cell. It is capable of persistent data storage at temperatures below 20 K in the form of extremely fast and energy-efficient switching between insulator and metallic states using electrical pulses. The pTron cell comprises a TaS2-based charge configuration memory (CCM) device in parallel with a superconducting nanocryotron (nTron) amplifier device, which addresses the CCM device, amplifies the driving signals and enables the coupling of the pTron cell with single flux quantum (SFQ) logic.
To carry out the measurements, a dedicated measurement set-up had to be designed and software for controlling multiple different instruments developed. The set-up was used to characterise several different CCM and nTron samples. Noise has been shown to have a negative impact on cell performance, so a lot of time has been spent on reducing it. Based on the data obtained, we assembled a pTron memory cell from CCM and nTron devices and demonstrated the writing process for the first time with partial success. Using a 1µs long voltage pulse, we changed the electrical resistance of the sample from 6.90kΩ to 1.78kΩ, which is satisfactory but leaves room for improvement. Based on these findings, further research work on the pTron memory cell is to be expected.
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