Voltage-controlled Hubbard spin transistor

TL;DR

This paper introduces a voltage-controlled spin transistor based on the Hubbard model that manipulates quantum spin information, enabling quantum computing operations with high speed and resilience.

Contribution

It presents a novel quantum spin transistor design using Hubbard model physics, allowing fast switching between open and closed modes for quantum information processing.

Findings

Switching time within a fraction of the operation time

Resilience against system imperfections

Potential for quantum dot array applications

Abstract

Transistors are key elements for enabling computational hardware in both classical and quantum domains. Here, we propose a voltage-gated spin transistor using itinerant electrons in the Hubbard model which acts at the level of single electron spins. Going beyond classical spintronics, it enables the controlling of the flow of quantum information between distant spin qubits. The transistor has two modes of operation, open and closed, which are realized by two different charge configurations in the gate of the transistor. In the closed mode, the spin information between source and drain is blocked while in the open mode we have free spin information exchange. The switching between the modes takes place within a fraction of the operation time which allows for several subsequent operations within the coherence time of the transistor. The system shows good resilience against several imperfections and opens up a practical application for quantum dot arrays.