Experiment Setup

Mitsuyoshi Kamba

Masanori Sato

We propose a new signaling system using the experimental setup of Wheeler's delayed-choice experiment previously carried out. In the delayed-choice experiment, the experimental setup shows a wave property or a particle property at the time when the experimental conditions of the wave-particle duality of photons are chosen. Choice signals can be used as transmitting signals and the wave-particle duality of photons is used as receiving signals. For example, if we choose the wave property of a photon as a transmitting signal, we detect the interference of the wave at the detector that can be used as a receiving signal. Therefore, the experimental setup of the delayed-choice experiment can transmit information through interference.

Roel Kassies, Aufried T. M. Lenferink, Ine M. J. Segers‐Nolten +1 more

We have designed and constructed a prism setup for multiple-color confocal fluorescence experiments. The prism setup permits easy selection of any color or any combination of colors from a multicolor light source, such as a mixed-gas argon-krypton-ion laser. The selected colors emerging from the prism setup are, by design, optimally overlapped in the focus of a high-numerical-aperture objective, such as that commonly used in single-molecule fluorescence experiments. The various excitation powers can be easily adjusted in this setup. We will exemplify the potential of this setup in single-molecule fluorescence emission spectroscopy.

Jamie Ryan Gardner

Shahin Tajik

Mario Krenn, Xuemei Gu, Anton Zeilinger

We show a surprising link between experimental setups to realize high-dimensional multipartite quantum states and graph theory. In these setups, the paths of photons are identified such that the photon-source information is never created. We find that each of these setups corresponds to an undirected graph, and every undirected graph corresponds to an experimental setup. Every term in the emerging quantum superposition corresponds to a perfect matching in the graph. Calculating the final quantum state is in the #P-complete complexity class, thus it cannot be done efficiently. To strengthen the link further, theorems from graph theory-such as Hall's marriage problem-are rephrased in the language of pair creation in quantum experiments. We show explicitly how this link allows one to answer questions about quantum experiments (such as which classes of entangled states can be created) with graph theoretical methods, and how to potentially simulate properties of graphs and networks with quantum experiments (such as critical exponents and phase transitions).