Temperature Effect on the Operation of Elementary Quantum-Dot Spin Gates by the Example of the NOT-AND Gate

TL;DR

This paper investigates how temperature impacts the functionality of quantum-dot spin gates, specifically the NOT-AND gate, revealing significant challenges for practical implementation due to high magnetic field requirements at low temperatures.

Contribution

It provides a theoretical analysis showing the impracticality of current quantum-dot spin gates for logic operations at finite temperatures, highlighting temperature as a major obstacle.

Findings

High magnetic fields needed at low temperatures for gate operation

Finite temperature effects hinder ground state calculations in spin gates

Challenges are common across all spin gate types

Abstract

The effect of temperature on the operation of the elementary quantum-dot spin gates for single-electron computing is studied theoretically within the framework of the Hubbard model by the example of the NOT-AND gate. The calculated values of the uniform external magnetic field necessary to realize the whole truth table proved to be unreasonably high for the implementation of the NOT-AND logical function even at the liquid helium temperature. This result appears to be common to all spin gates. Thus, finite temperatures seem to be a serious obstacle for the practical realization of ground state calculations in quantum dot spin gates.