The goal of this project is to develop a gate-tunable, scalable, and topologically-protectable supercurrent qubit and to integrate it into a quantum circuit for applications in the fields of quantum information technology and topological phenomena. The nano-hybrid supercurrent transistors are superconducting quantum analogue of a transistor and allow for unprecedented control of both the supercurrent magnitude and the current-phase relation by applying a voltage on a gate electrode. In the first stage of the project we will investigate topological insulator (TI) nanowires and a range of superconductors in order to detect Majorana fermion state in TI. At later stages, we plan to explore integration of these topological supercurrent transistor into the gate-tunable quantum bits (qubits) for practical applications in quantum information technology, exploring topological quantum computation. This project will help establishing a solid-state platform for developing topological supercurrent qubits.
In this Project, we aim to develop gate-tunable superconducting qubits made of one-dimensional (1D) topological insulator (TI) nanowires (NWs). Topological surface state in TI NW provides a topologically protectable channel for the supercurrent flow via the superconducting proximity effect. Since the supercurrent and Josephson coupling energy can be controlled by an electrostatic gate, we can form a topological supercurrent transistor (TST). Combination of TST with an on-chip microwave resonator will be a novel building block for controlling quantum bits (qubits) coherently. Our device scheme satisfies the requirements of gate tunable, scalable and topologically protectable qubits, which will be essential for topological quantum information process to come in the near future.