Constructing Qubits in Physical Systems
Quantum Physics
2009-11-07 v1
Abstract
The notion of a qubit is ubiquitous in quantum information processing. In spite of the simple abstract definition of qubits as two-state quantum systems, identifying qubits in physical systems is often unexpectedly difficult. There are an astonishing variety of ways in which qubits can emerge from devices. What essential features are required for an implementation to properly instantiate a qubit? We give three typical examples and propose an operational characterization of qubits based on quantum observables and subsystems.
Cite
@article{arxiv.quant-ph/0101090,
title = {Constructing Qubits in Physical Systems},
author = {Lorenza Viola and Emanuel Knill and Raymond Laflamme},
journal= {arXiv preprint arXiv:quant-ph/0101090},
year = {2009}
}
Comments
16 pages, no figures; IoP LaTeX2e style. Submitted to J. Phys. A: Math. Gen