Dr. Christopher Bauerle seminar
講師氏名：Dr. Christopher Bauerle (Directeur de Recherches au CNRS)
所属：Institut Neel-CNRS and Universite Joseph Fourier,
講演タイトル：From flying qubits with ballistic electrons towards
quantum optics with flying electrons
Abstract：Coherent manipulation of qubits, creation of quantum entanglement, and coherent transfer of quantum information are the core of quantum information technology. Employed with confined quantum states, a solid-state system is considered to have advantages on qubit manipulation and scalability. However, coherent transfer of quantum information over a long distance in a solid-state system is still a big challenge.
In this talk, I will report on the realization of a solid-state flying qubit, employing an Aharonov-Bohm (AB) ring connected to two-channel wires with tunable tunnel coupling . Quantum information in form of a flying qubit state is transferred over 6.5 μm distance within 40 ps. In addition to its application to quantum information, this original system can also act as a true two-path interferometer and allows us to address important problems of mesoscopic physics such as the phase shift across a Kondo impurity .
I will then show how such a system could be used to realize quantum optics experiments with single flying electrons. We demonstrate the first step towards this goal, namely the on demand single electron transfer between two distant quantum dots with very high fidelity using a sound wave [3,4]. Combining both schemes, this technology is opening an exciting platform for the transfer of quantum optics experiments to on chip solid-state devices
 M. Yamamoto, S. Takada, C. B?uerle, K. Watanabe, A. D. Wieck & S. Tarucha,
Nature Nanotechnology 7, 247-251 (2012);
 S. Takada, C. B?uerle, M. Yamamoto, K. Watanabe, S. Hermelin, T. Meunier, A. Alex, A. Weichselbaum,
J. von Delft, A.D. Wieck, S. Tarucha (in preparation)
 S. Hermelin, S. Takada, M. Yamamoto, S. Tarucha, A. D. Wieck, L. Saminadayar,
C. B?uerle and T. Meunier, Nature, 477, 7365 (2011)
 R. Mc Nail et al., Nature, 477, 7369 (2011)