Ground state structure and conductivity of quantum wires of infinite length and finite width

• Published in: arXiv.org
• Main Authors: Malet, Francesc, Pi, Marti, Barranco, Manuel, Lipparini, Enrico
• Format: Paper
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 15.11.2005
• Subjects: Compressibility; Confining; Electron density; Ground state; Physical properties; Quantum wires; Resistance
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.0511378

We have studied the ground state structure of quantum strips within the local spin-density approximation, for a range of electronic densities between \(\sim\) 5\(\times10^4\) and 2\(\times10^6\) cm\(^{-1}\) and several strengths of the lateral confining potential. The results have been used to address the conductance \(G\) of quantum strips. At low density, when only one subband is occupied, the system is fully polarized and \(G\) takes a value which is close to 0.7(2e\(^2/h\)), decreasing with increasing electron density in agreement with experiments. At higher densities the system becomes paramagnetic and \(G\) takes a value near (2e\(^2/h\)), showing a similar decreasing behaviour with increasing electron density. In both cases, the physical parameter that determines the value of the conductance is the ratio \(K/K_0\) of the compressibility of the system over the free one.