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Canted phase in double quantum dots

David Sanchez·L. Brey·Gloria Platero
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Abstract

We perform a Hartree-Fock calculation in order to describe the ground state of a vertical double quantum dot in the absence of magnetic fields parallel to the growth direction. Intra- and interdot exchange interactions determine the singlet or triplet character of the system as the tunneling is tuned. At finite Zeeman splittings due to in-plane magnetic fields, we observe the continuous quantum phase transition from ferromagnetic to symmetric phase through a canted antiferromagnetic state. The latter is obtained even at zero Zeeman energy for an odd electron number.

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David Sanchez, L. Brey, Gloria Platero. 2001-02-28. Canted phase in double quantum dots. https://doi.org/10.1103/physrevb.64.235304

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