title: Observation of a quantum Cheshire Cat in a matter-wave interferometer experiment.
abstract: From its very beginning, quantum theory has been revealing extraordinary and counter-intuitive phenomena, such as wave-particle duality, Schrödinger cats and quantum non-locality. Another paradoxical phenomenon found within the framework of quantum mechanics is the 'quantum Cheshire Cat': if a quantum system is subject to a certain pre- and postselection, it can behave as if a particle and its property are spatially separated. It has been suggested to employ weak measurements in order to explore the Cheshire Cat's nature. Here we report an experiment in which we send neutrons through a perfect silicon crystal interferometer and perform weak measurements to probe the location of the particle and its magnetic moment. The experimental results suggest that the system behaves as if the neutrons go through one beam path, while their magnetic moment travels along the other.
authors: Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna, Austria.
authors: Tobias
authors: T
authors: Denkmayr
authors: Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna, Austria.
authors: Hermann
authors: H
authors: Geppert
authors: Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna, Austria.
authors: Stephan
authors: S
authors: Sponar
authors: 1] Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna, Austria [2] Institut Laue-Langevin, 71 Avenue des Martyrs, CS 20156, 38042 Grenoble Cedex 9, France.
authors: Hartmut
authors: H
authors: Lemmel
authors: Laboratoire de Physique Théorique et Modélisation, CNRS Unité 8089, Université de Cergy-Pontoise, 95302 Cergy-Pontoise, France.
authors: Alexandre
authors: A
authors: Matzkin
authors: Institute for Quantum Studies and Schmid College of Science and Technology, Chapman University, 1 University Drive, Orange, California 92866, USA.
authors: Jeff
authors: J
authors: Tollaksen
authors: Atominstitut, Vienna University of Technology, Stadionallee 2, 1020 Vienna, Austria.
authors: Yuji
authors: Y
authors: Hasegawa