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arXiv · 1803.00326

Tuning the two-electron hybridization and spin states in parallel-coupled InAs quantum dots

Malin Nilsson·Florinda Viñas Boström·Sebastian Lehmann·Kimberly A. Dick·Martin Leijnse·Claes Thelander
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Abstract

We study spin transport in the one- and two-electron regimes of parallel-coupled double quantum dots (DQDs). The DQDs are formed in InAs nanowires by a combination of crystal-phase engineering and electrostatic gating, with an interdot tunnel coupling ($t$) tunable by one order of magnitude. Large single-particle energy separations (up to 10 meV) and $|g^*|$ factors ($\sim$10) enable detailed studies of the $B$-field-induced transition from a singlet-to-triplet ground state as a function of $t$. In particular, we investigate how the magnitude of the spin-orbit-induced singlet-triplet anticrossing depends on $t$. For cases of strong coupling, we find values of 230 $\mu$eV for the anticrossing using excited-state spectroscopy. Experimental results are reproduced by calculations based on rate equations and a DQD model including a single orbital in each dot.

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Malin Nilsson, Florinda Viñas Boström, Sebastian Lehmann, Kimberly A. Dick, Martin Leijnse, Claes Thelander. 2018-03-01. Tuning the two-electron hybridization and spin states in parallel-coupled InAs quantum dots. https://doi.org/10.1103/physrevlett.121.156802

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