Two-electron quantum dot in tilted magnetic fields: Sensitivity to the confinement model
2013 (English)In: European Physical Journal B: Condensed Matter Physics, ISSN 1434-6028, E-ISSN 1434-6036, Vol. 86, no 10, 430- p.Article in journal (Refereed) Published
Semiconductor quantum dots are conventionally treated within the effective-mass approximation and a harmonic model potential in the two-dimensional plane for the electron confinement. The validity of this approach depends on the type of the quantum-dot device as well as on the number of electrons confined in the system. Accurate modeling is particularly demanding in the few-particle regime, where screening effects are diminished and thus the system boundaries may have a considerable effect on the confining potential. Here we solve the numerically exact two-electron states in both harmonic and hard-wall model quantum dots subjected to tilted magnetic fields. Our numerical results enable direct comparison against experimental singlet-triplet energy splittings. Our analysis shows that hard and soft wall models produce qualitatively different results for quantum dots exposed to tilted magnetic fields. Hence, we are able to address the sensitivity of the two-body phenomena to the modeling, which is of high importance in realistic spin-qubit design.
Place, publisher, year, edition, pages
2013. Vol. 86, no 10, 430- p.
Condensed Matter Physics
IdentifiersURN: urn:nbn:se:su:diva-96095DOI: 10.1140/epjb/e2013-40677-xISI: 000325608100003OAI: oai:DiVA.org:su-96095DiVA: diva2:664194
Nordforsk Research Council of Norway (RCN;) Swedish research council (VR); Academy of Finland; European Community's FP7 through the CRONOS project 280879 2013-11-142013-11-112014-04-24Bibliographically approved