Spin-vortex-induced Loop Current Qubits: Gate Control and Readout Using External Current Feeding

We theoretically consider the quantum gate control and readout of qubits composed of spin-vortex-induced loop currents (SVILCs) by external current feeding, where the SVILCs are topologically protected loop currents predicted to exist in cuprate superconductors. We consider two types of architectures to use SVILC qubits: One is composed of stacked two-dimensional CuO2 bulk layers, and the other is composed of CuO2 islands connected by artificial quantum dots, where each CuO2 island is composed of one surface and one bulk layer. Qubit controls are realized by the application of an external magnetic field, and the feeding of external currents that cause Landau-Zener (LZ)-type transitions. We also show that artificial quantum dot states may be used for the readout.

Automated summary

This article theoretically considers the quantum gate control and readout of qubits composed of spin-vortex-induced loop currents (SVILCs) using external current feeding. Two types of SVILC qubit architectures are considered: one composed of stacked two-dimensional CuO2 bulk layers, and the other composed of CuO2 islands connected by artificial quantum dots. Qubit controls are achieved through the application of an external magnetic field and the feeding of external currents that cause Landau-Zener (LZ)-type transitions. The use of artificial quantum dot states for readout is also demonstrated.