2025/12/09 by Tanamoto, Tetsufumi, Ono, Keiji
Computer Science · Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum Physics (quant-ph) #Quantum and electron transport phenomena #Quantum-Dot Cellular Automata
paper · doi:10.48550/arxiv.2512.08152
openalex publication_date 2025/12/09 · openalex created_date 2025/12/11 · openalex updated_date 2026/07/28
We theoretically investigated the readout process of a spin--qubit structure based on a gate-all-around (GAA) transistor. Our study focuses on a logical qubit composed of two physical qubits. Different spin configurations result in different charge distributions, which subsequently influence the electrostatic effects on the GAA transistor. Consequently, the current flowing through the GAA transistor depends on the qubit's state. We calculated the current-voltage characteristics of the three-dimensional configurations of the qubit and GAA structures, using technology computer-aided design (TCAD) simulations. Moreover, we performed circuit simulations using the Simulation Program with Integrated Circuit Emphasis (SPICE) to investigate whether a readout circuit made from complementary metal--oxide semiconductor (CMOS) transistors can amplify the weak signals generated by the qubits. Our findings indicate that, by dynamically controlling the applied voltage within a properly designed circuit, the readout can be detected effectively based on a conventional sense amplifier.