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arXiv · 1811.03907

Microwave cavity detected spin blockade in a few electron double quantum dot

A. J. Landig·J. V. Koski·P. Scarlino·C. Reichl·W. Wegscheider·A. Wallraff·K. Ensslin·T. Ihn
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Abstract

We investigate spin states of few electrons in a double quantum dot by coupling them weakly to a magnetic field resilient NbTiN microwave resonator. We observe a reduced resonator transmission if resonator photons and spin singlet states interact. This response vanishes in a magnetic field once the quantum dot ground state changes from a spin singlet into a spin triplet state. Based on this observation, we map the two-electron singlet-triplet crossover by resonant spectroscopy. By measuring the resonator only, we observe Pauli spin blockade known from transport experiments at finite source-drain bias and detect an unconventional spin blockade triggered by the absorption of resonator photons.

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A. J. Landig, J. V. Koski, P. Scarlino, C. Reichl, W. Wegscheider, A. Wallraff, K. Ensslin, T. Ihn. 2018-11-09. Microwave cavity detected spin blockade in a few electron double quantum dot. https://doi.org/10.1103/physrevlett.122.213601

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