Quantum Manipulations of Small Josephson Junctions

TL;DR

This paper explores the use of low-capacitance Josephson junction arrays as potential quantum bits for quantum computing, focusing on their controllability and coherence properties.

Contribution

It proposes Josephson junction arrays as physical realizations of quantum bits and analyzes their control and coherence for quantum computation.

Findings

Phase coherence time is sufficiently long for experiments.

Gate voltages enable quantum state manipulation.

Arrays can serve as quantum computational elements.

Abstract

Low-capacitance Josephson junction arrays in the parameter range where single charges can be controlled are suggested as possible physical realizations of the elements which have been considered in the context of quantum computers. We discuss single and multiple quantum bit systems. The systems are controlled by applied gate voltages, which also allow the necessary manipulation of the quantum states. We estimate that the phase coherence time is sufficiently long for experimental demonstration of the principles of quantum computation.