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arXiv · 1503.02928

Transport Spectroscopy of a Spin-Coherent Dot-Cavity System

Clemens Rössler·David Oehri·Oded Zilberberg·Gianni Blatter·Matija Karalic·Jana Pijnenburg·Andrea Hofmann·Thomas Ihn·Klaus Ensslin·Christian Reichl·Werner Wegscheider
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Abstract

Quantum engineering requires controllable artificial systems with quantum coherence exceeding the device size and operation time. This can be achieved with geometrically confined low-dimensional electronic structures embedded within ultraclean materials, with prominent examples being artificial atoms (quantum dots) and quantum corrals (electronic cavities). Combining the two structures, we implement a mesoscopic coupled dot-cavity system in a high-mobility two-dimensional electron gas, and obtain an extended spin-singlet state in the regime of strong dot-cavity coupling. Engineering such extended quantum states presents a viable route for nonlocal spin coupling that is applicable for quantum information processing.

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Clemens Rössler, David Oehri, Oded Zilberberg, Gianni Blatter, Matija Karalic, Jana Pijnenburg, Andrea Hofmann, Thomas Ihn, Klaus Ensslin, Christian Reichl, Werner Wegscheider. 2015-09-01. Transport Spectroscopy of a Spin-Coherent Dot-Cavity System. https://doi.org/10.1103/physrevlett.115.166603

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