Non-volatile ferroelectric superconducting field effect transistor

A ferroelectric-superconducting three-terminal device consisting of a YBa2Cu3O7-x (YBCO) base layer and a PbZrTiO3 (PZT) gate has been fabricated which acts as a ferroelectric-superconducting field effect transistor (FSuFET). The PZT/YBCO layers were deposited sequentially on an MgO (100) substrate by excimer laser deposition. The thickness of the YBCO layer was nominally 100nm and that of the PZT layer was 500nm. Both conventional DC measurements and a modified admittance spectroscopy method were used to characterize the device. The YBCO channel resistance has been shown to be modulated by over 25% dependent on the polarization of the PZT gate, the highest modulation shown to date. The polarization state and thus the channel state were retained for greater than 10(6) seconds. This was the first demonstration of non-volatility in such a superconducting logic device. The transient behavior of the ferroelectric-superconducting device has also been studied and shows four-state characteristics. The four states can be controlled by changing the PZT polarization state or switching of the YBCO channel from the superconducting state to the normal state.