arXiv:quant-ph/0212131 · Quantum Information and Computation

Non-empty quantum dot as a spin-entangler

Chih‐Lung Chou

Published Jul 1, 2003• 0 citations

Abstract

We consider a three-port single-level quantum dot system with one input and two output leads. Instead of considering an empty dot, we study the situations that two input electrons co-tunnel through the quantum dot occupied by one or two dot electrons. We show that electron entanglement can be generated via the co-tunneling processes when the dot is occupied by two electrons, yielding non-local spin-singlet states at the output leads. When the dot is occupied by a single electron, we show that by carefully selecting model parameters non-local spin-triplet electrons can also be obtained at the output leads if the final dot electron has the same spin as that of the initial dot electron.

DOI: 10.26421/qic3.4-2

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