Feasibility of 300 km Quantum Key Distribution with Entangled States (2010)
Scheidl, Thomas, Ursin, Rupert, Fedrizzi, Alessandro, Ramelow, Sven, Ma, Xiao-Song, Herbst, Thomas, ...
A significant limitation of practical quantum key distribution (QKD) setups is currently their limited operational range. It has recently been emphasized (X. Ma, C.-H. F. Fung, and H.-K. Lo., Phys....
Towards on-demand single-photon generation via active multiplexing (2010)
Ma, Xiao-song, Zotter, Stefan, Kofler, Johannes, Jennewein, Thomas, Zeilinger, Anton
An on-demand single-photon source is a fundamental building block in quantum science and technology. In a proof-of-principle experiment, we demonstrate on-demand single-photon generation via actively...
Heralded generation of entangled photon pairs (2010)
Barz, Stefanie, Cronenberg, Gunther, Zeilinger, Anton, Walther, Philip
Entangled photons are a crucial resource for quantum communication and linear optical quantum computation. Unfortunately, the applicability of many photon-based schemes is limited due to the...
Heralded generation of entangled photon pairs (2010)
Stefanie Barz, Gunther Cronenberg, Anton Zeilinger, Philip Walther
Some of the possible reasons for the presently existing statistically significant discrepancy between the experimental and the theoretical values of the electron (R- 2) would lead to fundamental...
Quantum key distribution and cryptography: a survey (2010)
Alléaume, Romain, Lütkenhaus, Norbert, Renner, Renato, Grangier, Philippe, Debuisschert, Thierry, Ribordy, Gregoire, ...
I will try to partially answer, based on a review on recent work, the following question: Can QKD and more generally quantum information be useful to cover some practical security requirements in...
Information Invariance and Quantum Probabilities (2009)
Brukner, Caslav, Zeilinger, Anton
We consider probabilistic theories in which the most elementary system, a two-dimensional system, contains one bit of information. The bit is assumed to be contained in any complete set of mutually...
Ma, Xiao-song, Qarry, Angie, Kofler, Johannes, Jennewein, Thomas, Zeilinger, Anton
We demonstrate hybrid entanglement of photon pairs via the experimental violation of a Bell inequality with two different degrees of freedom (DOF), namely the path (linear momentum) of one photon and...
High-fidelity transmission of entanglement over a high-loss freespace channel (2009)
Fedrizzi, Alessandro, Ursin, Rupert, Herbst, Thomas, Nespoli, Matteo, Prevedel, Robert, Scheidl, Thomas, ...
Quantum entanglement enables tasks not possible in classical physics. Many quantum communication protocols require the distribution of entangled states between distant parties. Here we experimentally...
Fully automated entanglement-based quantum cryptography system for telecom fiber networks (2009)
Treiber, Alexander, Poppe, Andreas, Hentschel, Michael, Ferrini, Daniele, Lorünser, Thomas, Querasser, Edwin, ...
We present a quantum key distribution (QKD) system based on polarisation entanglement for use in telecom fibers. A QKD exchange up to 50km was demonstrated in the laboratory with a secure key rate of...
Quantum teleportation and entanglement swapping with linear optics logic gates (2009)
Schmid, Christian, Kiesel, Nikolai, Weber, Ulrich K., Ursin, Rupert, Zeilinger, Anton, Weinfurter, Harald
Anti-symmetrization reveals hidden entanglement (2009)
Fedrizzi, Alessandro, Herbst, Thomas, Aspelmeyer, Markus, Barbieri, Marco, Jennewein, Thomas, Zeilinger, Anton
Anti-symmetrization reveals hidden entanglement (2009)
Fedrizzi, Alessandro, Herbst, Thomas, Aspelmeyer, Markus, Barbieri, Marco, Jennewein, Thomas, Zeilinger, Anton
Two-photon anti-bunching at a beamsplitter is only possible if the photons are entangled in a specific state, anti-symmetric in the spatial modes. Thus, observation of anti-bunching is an indication...
Anti-symmetrization reveals hidden entanglement (2009)
Fedrizzi, Alessandro, Herbst, Thomas, Aspelmeyer, Markus, Barbieri, Marco, Jennewein, Thomas, Zeilinger, Anton
Two-photon anti-bunching at a beamsplitter is only possible if the photons are entangled in a specific state, anti-symmetric in the spatial modes. Thus, observation of anti-bunching is an indication...
Mathematical undecidability and quantum randomness (2008)
Paterek, Tomasz, Kofler, Johannes, Prevedel, Robert, Klimek, Peter, Aspelmeyer, Markus, Zeilinger, Anton, ...
We propose a new link between mathematical undecidability and quantum physics. We demonstrate that the states of elementary quantum systems are capable of encoding mathematical axioms and show that...
Violation of local realism with freedom of choice (2008)
Scheidl, Thomas, Ursin, Rupert, Kofler, Johannes, Ramelow, Sven, Ma, Xiao-Song, Herbst, Thomas, ...
The predictions of quantum mechanics can be in striking contradiction with local realism if entanglement exists between distant systems. Bell's theorem shows that local realistic theories, such as...
Comment on: Testing the speed of 'spooky action at a distance' (2008)
Kofler, Johannes, Ursin, Rupert, Brukner, Caslav, Zeilinger, Anton
In a recent experiment, Salart et al. addressed the important issues of the speed of hypothetical communication and of reference frames in Bell-type experiments. The authors report that they...
High-fidelity entanglement swapping with fully independent sources (2008)
Kaltenbaek, Rainer, Prevedel, Robert, Aspelmeyer, Markus, Zeilinger, Anton
Entanglement swapping allows to establish entanglement between independent particles that never interacted nor share any common past. This feature makes it an integral constituent of quantum...
Quantum teleportation and entanglement swapping with linear optics logic gates (2008)
Schmid, Christian, Kiesel, Nikolai, Weber, Ulrich K., Ursin, Rupert, Zeilinger, Anton, Weinfurter, Harald
We report on the usage of a linear optics phase gate for distinguishing all four Bell states simultaneously in a quantum teleportation and entanglement swapping protocol. This is demonstrated by full...
Detection of hidden entanglement by photon anti-bunching (2008)
Fedrizzi, Alessandro, Herbst, Thomas, Aspelmeyer, Markus, Barbieri, Marco, Jennewein, Thomas, Zeilinger, Anton
Two-photon anti-bunching at a beamsplitter is only possible if the photons are entangled in one specific state, anti-symmetric in the modes. Thus, detection of anti-bunching is a direct indication of...
Space-QUEST: Experiments with quantum entanglement in space (2008)
Ursin, Rupert, Jennewein, Thomas, Kofler, Johannes, Perdigues, Josep M., Cacciapuoti, Luigi, De Matos, Clovis J., ...
The European Space Agency (ESA) has supported a range of studies in the field of quantum physics and quantum information science in space for several years, and consequently we have submitted the...
Multi-photon entanglement and interferometry (2008)
Pan, Jian-Wei, Chen, Zeng-Bing, Zukowski, Marek, Weinfurter, Harald, Zeilinger, Anton
Multi-photon interference reveals strictly non-classical phenomena. Thus in quantum information, a significant fraction of key experimental progresses achieved so far comes from multi-photon state...
Heralded generation of multiphoton entanglement (2008)
Walther, Philip, Aspelmeyer, Markus, Zeilinger, Anton
We present a scheme, based only on linear optics and standard photon detection, that allows to generate heralded multiphoton entangled states of arbitrary photon number from spontaneous parametric...
Photonic entanglement as a resource in quantum computation and quantum communication (2008)
Prevedel, Robert, Aspelmeyer, Markus, Brukner, Caslav, Jennewein, Thomas, Zeilinger, Anton
Entanglement is an essential resource in current experimental implementations for quantum information processing. We review a class of experiments exploiting photonic entanglement, ranging from...
Experimental verification of the feasibility of a quantum channel between Space and Earth (2008)
Villoresi, Paolo, Jennewein, Thomas, Tamburini, Fabrizio, Aspelmeyer, Markus, Bonato, Cristian, Ursin, Rupert, ...
Extending quantum communication to Space environments would enable to perform fundamental experiments on quantum physics as well as applications of quantum information at planetary and interplanetary...
Hübel, Hannes, Vanner, Michael R., Lederer, Thomas, Blauensteiner, Bibiane, Lorünser, Thomas, Poppe, Andreas, ...
We demonstrate non-degenerate down-conversion at 810 and 1550 nm for long-distance fiber based quantum communication using polarization entangled photon pairs. Measurements of the two-photon...
Quantum communications at ESA: Towards a space experiment on the ISS (2008)
Perdigues Armengol, Josep Maria, Furch, Bernhard, De Matos, Clovis Jacinto, Minster, Olivier, Cacciapuoti, Luigi, Pfennigbauer, Martin, ...
Plenary debate: Quantum effects in biology: trivial or not? (2008)
Abbott, Derek, Gea-Banacloche, Julio, Davies, Paul Charles William, Hameroff, Stuart, Zeilinger, Anton, Eisert, Jens, ...
Copyright © World Scientific Publishing Company
Plenary debate: Quantum effects in biology: trivial or not? (2008)
Abbott, Derek Zarir, Gea-Banacloche, Julio, Davies, Paul Charles William, Hameroff, Stuart, Zeilinger, Anton, Eisert, Jens, ...
Copyright © World Scientific Publishing Company
Plenary debate: Quantum effects in biology: trivial or not? (2008)
Abbott, Derek Zarir, Gea-Banacloche, Julio, Davies, Paul Charles William, Hameroff, Stuart, Zeilinger, Anton, Eisert, Jens, ...
Copyright © World Scientific Publishing Company
Plenary debate: Quantum effects in biology: trivial or not? (2008)
Abbott, Derek, Gea-Banacloche, Julio, Davies, Paul Charles William, Hameroff, Stuart, Zeilinger, Anton, Eisert, Jens, ...
Copyright © World Scientific Publishing Company
Going Beyond Bell's Theorem (2007)
Greenberger, Daniel M., Horne, Michael A., Zeilinger, Anton
Bell's Theorem proved that one cannot in general reproduce the results of quantum theory with a classical, deterministic local model. However, Einstein originally considered the case where one could...
Experimental realization of a quantum game on a one-way quantum computer (2007)
Prevedel, Robert, Stefanov, Andre, Walther, Philip, Zeilinger, Anton
We report the first demonstration of a quantum game on an all-optical one-way quantum computer. Following a recent theoretical proposal we implement a quantum version of Prisoner's Dilemma, where the...
Experimental test of nonlocal realistic theories without the rotational symmetry assumption (2007)
Paterek, Tomasz, Fedrizzi, Alessandro, Groeblacher, Simon, Jennewein, Thomas, Zukowski, Marek, Aspelmeyer, Markus, ...
We analyze the class of nonlocal realistic theories that was originally considered by Leggett [Found. Phys. 33, 1469 (2003)] and tested by us in a recent experiment [Nature (London) 446, 871 (2007)]....
How to create and detect N-dimensional entangled photons with an active phase hologram (2007)
Stuetz, Martin, Groeblacher, Simon, Jennewein, Thomas, Zeilinger, Anton
The experimental realization of multidimensional quantum states may lead to unexplored and interesting physics, as well as advanced quantum communication protocols. The orbital angular momentum of...
A wavelength-tunable fiber-coupled source of narrowband entangled photons (2007)
Fedrizzi, Alessandro, Herbst, Thomas, Poppe, Andreas, Jennewein, Thomas, Zeilinger, Anton
We demonstrate a wavelength-tunable, fiber-coupled source of polarization-entangled photons with extremely high spectral brightness and quality of entanglement. Using a 25 mm PPKTP crystal inside a...
Radiation-pressure self-cooling of a micromirror in a cryogenic environment (2007)
Groeblacher, Simon, Gigan, Sylvain, Boehm, Hannes R., Zeilinger, Anton, Aspelmeyer, Markus
We demonstrate radiation-pressure cavity-cooling of a mechanical mode of a micromirror starting from cryogenic temperatures. To achieve that, a high-finesse Fabry-Perot cavity (F\approx 2200) was...
An experimental test of non-local realism (2007)
Groeblacher, Simon, Paterek, Tomasz, Kaltenbaek, Rainer, Brukner, Caslav, Zukowski, Marek, Aspelmeyer, Markus, ...
Most working scientists hold fast to the concept of 'realism' - a viewpoint according to which an external reality exists independent of observation. But quantum physics has shattered some of our...
An experimental test of non-local realism (2007)
Simon Gröblacher, Tomasz Paterek, Rainer Kaltenbaek, Časlav Brukner, Marek Żukowski, Markus Aspelmeyer, ...
SECOQC White Paper on Quantum Key Distribution and Cryptography (2007)
Alleaume, Romain, Bouda, Jan, Branciard, Cyril, Debuisschert, Thierry, Dianati, Mehrdad, Gisin, Nicolas, ...
The SECOQC White Paper on Quantum Key Distribution and Cryptography is the outcome on a thorough consultation and discussion among the participants of the European project SECOQC (www.secoqc.net)....
High-speed linear optics quantum computing using active feed-forward (2007)
Prevedel, Robert, Walther, Philip, Tiefenbacher, Felix, Böhi, Pascal, Kaltenbaek, Rainer, Jennewein, Thomas, ...
As information carriers in quantum computing, photonic qubits have the advantage of undergoing negligible decoherence. However, the absence of any significant photon-photon interaction is problematic...
Experimental Demonstration of Free-Space Decoy-State Quantum Key Distribution over 144 km (2007)
Schmitt-Manderbach, Tobias, Weier, Henning, Fürst, Martin, Ursin, Rupert, Tiefenbacher, Felix, Scheidel, Thomas, ...
Experimental test of nonlocal realistic theories without the rotational symmetry assumption (2007)
Paterek, Tomasz, Fedrizzi, Alessandro, Gröblacher, Simon, Jennewein, Thomas, Żukowski, Marek, Aspelmeyer, Markus, ...
We analyze the class of nonlocal realistic theories that was originally considered by Leggett [Found. Phys. 33, 1469 (2003)] and tested by us in a recent experiment [Nature (London) 446, 871 (2007)]....
A wavelength-tunable fiber-coupled source of narrowband entangled photons (2007)
Fedrizzi, Alessandro, Herbst, Thomas, Poppe, Andreas, Jennewein, Thomas, Zeilinger , Anton
We demonstrate a wavelength-tunable, fiber-coupled source of polarization- entangled photons with extremely high spectral brightness and quality of entanglement. Using a 25 mm PPKTP crystal inside a...
Experimental test of nonlocal realistic theories without the rotational symmetry assumption (2007)
Paterek, Tomasz, Fedrizzi, Alessandro, Gröblacher, Simon, Jennewein, Thomas, Żukowski, Marek, Aspelmeyer, Markus, ...
We analyze the class of nonlocal realistic theories that was originally considered by Leggett [Found. Phys. 33, 1469 (2003)] and tested by us in a recent experiment [Nature (London) 446, 871 (2007)]....
A wavelength-tunable fiber-coupled source of narrowband entangled photons (2007)
Fedrizzi, Alessandro, Herbst, Thomas, Poppe, Andreas, Jennewein, Thomas, Zeilinger , Anton
We demonstrate a wavelength-tunable, fiber-coupled source of polarization- entangled photons with extremely high spectral brightness and quality of entanglement. Using a 25 mm PPKTP crystal inside a...
Experimental test of nonlocal realistic theories without the rotational symmetry assumption (2007)
Paterek, Tomasz, Fedrizzi, Alessandro, Gröblacher, Simon, Jennewein, Thomas, Żukowski, Marek, Aspelmeyer, Markus, ...
We analyze the class of nonlocal realistic theories that was originally considered by Leggett [Found. Phys. 33, 1469 (2003)] and tested by us in a recent experiment [Nature (London) 446, 871 (2007)]....
A wavelength-tunable fiber-coupled source of narrowband entangled photons (2007)
Fedrizzi, Alessandro, Herbst, Thomas, Poppe, Andreas, Jennewein, Thomas, Zeilinger , Anton
We demonstrate a wavelength-tunable, fiber-coupled source of polarization- entangled photons with extremely high spectral brightness and quality of entanglement. Using a 25 mm PPKTP crystal inside a...
Experimental interference of independent photons (2006)
Kaltenbaek, Rainer, Blauensteiner, Bibiane, Zukowski, Marek, Aspelmeyer, Markus, Zeilinger, Anton
Interference of photons emerging from independent sources is essential for modern quantum information processing schemes, above all quantum repeaters and linear-optics quantum computers. We report an...
Experimental Quantum Cryptography with Qutrits (2005)
Groeblacher, Simon, Jennewein, Thomas, Vaziri, Alipasha, Weihs, Gregor, Zeilinger, Anton
We produce two identical keys using, for the first time, entangled trinary quantum systems (qutrits) for quantum key distribution. The advantage of qutrits over the normally used binary quantum...
A Bell Theorem Without Inequalities for Two Particles, Using Inefficient Detectors (2005)
Greenberger, Daniel, Horne, Michael, Zeilinger, Anton, Zukowski, Marek
We again consider (as in a companion paper) an entangled two-particle state that is produced from two independent down-conversion sources by the process of "entanglement-swapping", so that the...
A Bell Theorem Without Inequalities for Two Particles, Using Efficient Detectors (2005)
Greenberger, Daniel M., Horne, Michael, Zeilinger, Anton
We consider an entangled two-particle state that is produced from two independent down-conversion sources by the process of "entanglement-swapping", so that the particles have never met. We prove a...
Experimental Entangled Entanglement (2005)
Walther, Philip, Resch, Kevin J., Brukner, Caslav, Zeilinger, Anton
All previous tests of local realism have studied correlations between single-particle measurements. In the present experiment, we have performed a Bell experiment on three particles in which one of...
Experimental violation of a cluster state Bell inequality (2005)
Walther, Philip, Aspelmeyer, Markus, Resch, Kevin J., Zeilinger, Anton
Cluster states are a new type of multiqubit entangled states with entanglement properties exceptionally well suited for quantum computation. In the present work, we experimentally demonstrate that...
Il velo di Einstein, il nuovo mondo della fisica quantistica, Anton Zeilinger, traduzione di Lorenzo Lilli. . - Torino . NALUAF000800. , Einaudi. NAEDAF00002046, 2005.
Full characterization of a three-photon GHZ state using quantum state tomography (2004)
Resch, Kevin J., Walther, Philip, Zeilinger, Anton
We have performed the first experimental tomographic reconstruction of a three-photon polarization state. Quantum state tomography is a powerful tool for fully describing the density matrix of a...
Experimental Realization of a Photonic Bell-State Analyzer (2004)
Walther, Philip, Zeilinger, Anton
Efficient teleportation is a crucial step for quantum computation and quantum networking. In the case of qubits, four different entangled Bell states have to be distinguished. We have realized a...
Crucial Role of Quantum Entanglement in Bulk Properties of Solids (2004)
Brukner, Caslav, Vedral, Vlatko, Zeilinger, Anton
We demonstrate that the magnetic susceptibility of strongly alternating antiferromagnetic spin-1/2 chains is an entanglement witness. Specifically, magnetic susceptibility of copper nitrate (CN)...
Jennewein, Thomas, Ursin, Rupert, Aspelmeyer, Markus, Zeilinger, Anton
We demonstrate an experiment on entanglement swapping using an optimal Bell-state measurement capable of identifying two of the four Bell-states for polarization entangled photons, which is the...
Böhm, Hannes R., Böhm, Paul S., Aspelmeyer, Markus, Brukner, Časlav, Zeilinger, Anton
We suggest that the randomness of the choices of measurement basis by Alice and Bob provides an additional important resource for quantum cryptography. As a specific application, we present a novel...
Communications: Quantum teleportation across the Danube (2004)
Rupert Ursin, Thomas Jennewein, Markus Aspelmeyer, Rainer Kaltenbaek, Michael Lindenthal, Philip Walther, ...
Complementarity and Information in "Delayed-choice for entanglement swapping" (2004)
Brukner, Caslav, Aspelmeyer, Markus, Zeilinger, Anton
Building on Peres's idea of "Delayed-choice for extanglement swapping" we show that even the degree to which quantum systems were entangled can be defined after they have been registered and may even...
Realization of a photonic CNOT gate sufficient for quantum computation (2004)
Gasparoni, Sara, Pan, Jian-Wei, Walther, Philip, Rudolph, Terry, Zeilinger, Anton
We report the first experimental demonstration of a quantum controlled-NOT gate for different photons, which is classically feed-forwardable. In the experiment, we achieved this goal with the use...
Decoherence of matter waves by thermal emission of radiation (2004)
Hackermueller, Lucia, Hornberger, Klaus, Brezger, Bjoern, Zeilinger, Anton, Arndt, Markus
Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause...
De Broglie Wavelength of a Nonlocal Four-Photon (2003)
Walther, Philip, Pan, Jian-Wei, Aspelmeyer, Markus, Ursin, Rupert, Gasparoni, Sara, Zeilinger, Anton
Superposition is one of the most distinct features of quantum theory and has been demonstrated in numerous realizations of Young's classical double-slit interference experiment and its analogues....
The wave nature of biomolecules and fluorofullerenes (2003)
Hackermueller, Lucia, Uttenthaler, Stefan, Hornberger, Klaus, Reiger, Elisabeth, Brezger, Bjoern, Zeilinger, Anton, ...
We demonstrate quantum interference for tetraphenylporphyrin, the first biomolecule exhibiting wave nature, and for the fluorofullerene C60F48 using a near-field Talbot-Lau interferometer. For the...
Proof-of-Concept Experiments for Quantum Physics in Space (2003)
Kaltenbaek, Rainer, Aspelmeyer, Markus, Jennewein, Thomas, Brukner, Caslav, Pfennigbauer, Martin, Leeb, Walter R., ...
Quantum physics experiments in space using entangled photons and satellites are within reach of current technology. We propose a series of fundamental quantum physics experiments that make...
Experimental nonlinear sign shift for linear optics quantum computation (2003)
Sanaka, Kaoru, Jennewein, Thomas, Pan, Jian-Wei, Resch, Kevin, Zeilinger, Anton
We have realized the nonlinear sign shift (NS) operation for photonic qubits.This operation shifts the phase of two photons reflected by a beam splitter using an extra single photon and measurement....
Decoherence in a Talbot Lau interferometer: the influence of molecular scattering (2003)
Hackermueller, Lucia, Hornberger, Klaus, Brezger, Bjoern, Zeilinger, Anton, Arndt, Markus
We study the interference of C70 fullerenes in a Talbot-Lau interferometer with a large separation between the diffraction gratings. This permits the observation of recurrences of the interference...
Long-Distance Quantum Communication with Entangled Photons using Satellites (2003)
Aspelmeyer, Markus, Jennewein, Thomas, Pfennigbauer, Martin, Leeb, Walter, Zeilinger, Anton
The use of satellites to distribute entangled photon pairs (and single photons) provides a unique solution for long-distance quantum communication networks. This overcomes the principle limitations...
Jennewein, Thomas, Weihs, Gregor, Pan, Jian-Wei, Zeilinger, Anton
Ryff's Comment raises the question of the meaning of the quantum state. We argue that the quantum state is just the representative of information available to a given observer. Then Ryff's...
Collisional decoherence observed in matter wave interferometry (2003)
Hornberger, Klaus, Uttenthaler, Stefan, Brezger, Bjoern, Hackermueller, Lucia, Arndt, Markus, Zeilinger, Anton
We study the loss of spatial coherence in the extended wave function of fullerenes due to collisions with background gases. From the gradual suppression of quantum interference with increasing gas...
Concentration of higher dimensional entanglement (2003)
Vaziri, Alipasha, Pan, Jian-Wei, Jennewein, Thomas, Weihs, Gregor, Zeilinger, Anton
Enhancement of entanglement enhancement is necessary for most quantum communication protocols many of which are defined in Hilbert spaces larger than two. In this work we present the experimental...
Experimental realization of freely propagating teleported qubits (2003)
Jian-Wei Pan, Sara Gasparoni, Markus Aspelmeyer, Thomas Jennewein, Anton Zeilinger
Free-Space Optical Quantum Key Distribution Using Intersatellite (2003)
Martin Pfennigbauer, Walter R. Leeb, Markus Aspelmeyer, Thomas Jennewein, Anton Zeilinger
Communication schemes employing quantum entanglement open a wide field of possible applications with properties outperforming their classical counterparts. Promising examples are quantum key...
Information and fundamental elements of the structure of quantum theory (2002)
Brukner, Caslav, Zeilinger, Anton
Niels Bohr wrote: "There is no quantum world. There is only an abstract quantum physical description. It is wrong to think that the task of physics is to find out how Nature is. Physics concerns what...
All-Versus-Nothing Violation of Local Realism for Two Entangled Photons (2002)
Chen, Zeng-Bing, Pan, Jian-Wei, Zhang, Yong-De, Brukner, Caslav, Zeilinger, Anton
It is shown that the Greenberger-Horne-Zeilinger theorem can be generalized to the case with only two entangled particles. The reasoning makes use of two photons which are maximally entangled both in...
Violation of Bell's inequality: criterion for quantum communication complexity advantage (2002)
Brukner, Caslav, Zukowski, Marek, Pan, Jian-Wei, Zeilinger, Anton
We prove that for every Bell's inequality and for a broad class of protocols, there always exists a multi-party communication complexity problem, for which the protocol assisted by states which...
Brukner, Caslav, Kim, Myungshik S., Pan, Jian-Wei, Zeilinger, Anton
We establish a mapping between a continuous variable (CV) quantum system and a discrete quantum system of arbitrary dimension. This opens up the general possibility to perform any quantum information...
Time-Reversed EPR and the Choice of Histories in Quantum Mechanics (2002)
Elitzur, Avshalom C., Dolev, Shahar, Zeilinger, Anton
When a single photon is split by a beam splitter, its two `halves' can entangle two distant atoms into an EPR pair. We discuss a time-reversed analogue of this experiment where two distant sources...
Quantum communication complexity protocol with two entangled qutrits (2002)
Brukner, Caslav, Zukowski, Marek, Zeilinger, Anton
We formulate a two-party communication complexity problem and present its quantum solution that exploits the entanglement between two qutrits. We prove that for a broad class of protocols the...
Experimental Nonlocality Proof of Quantum Teleportation and Entanglement Swapping (2002)
Jennewein, Thomas, Weihs, Gregor, Pan, Jian-Wei, Zeilinger, Anton
Quantum teleportation strikingly underlines the peculiar features of the quantum world. We present an experimental proof of its quantum nature, teleporting an entangled photon with such high quality...
Young's experiment and the finiteness of information (2002)
Brukner, Caslav, Zeilinger, Anton
Young's experiment is the quintessential quantum experiment. It is argued here that quantum interference is a consequence of the finiteness of information. The observer has the choice whether that...
Superpositions of the Orbital Angular Momentum for Applications in Quantum Experiments (2001)
Vaziri, Alipasha, Weihs, Gregor, Zeilinger, Anton
Two different experimental techniques for preparation and analyzing superpositions of the Gaussian and Laguerre-Gassian modes are presented. This is done exploiting an interferometric method on the...
Diffraction of complex molecules by structures made of light (2001)
Nairz, Olaf, Brezger, Björn, Arndt, Markus, Zeilinger, Anton
We demonstrate that structures made of light can be used to coherently control the motion of complex molecules. In particular, we show diffraction of the fullerenes C60 and C70 at a thin grating...
Probabilistic instantaneous quantum computation (2001)
Brukner, Caslav, Pan, Jian-Wei, Simon, Christoph, Weihs, Gregor, Zeilinger, Anton
The principle of teleportation can be used to perform a quantum computation even before its quantum input is defined. The basic idea is to perform the quantum computation at some earlier time with...
The essence of entanglement (2001)
Brukner, Caslav, Zukowski, Marek, Zeilinger, Anton
Entanglement, according to Erwin Schroedinger the essence of quantum mechanics, is at the heart of the Einstein-Podolsky-Rosen paradox and of the so called quantum-nonlocality - the fact that a local...
Experimental verification of the Heisenberg uncertainty principle for hot fullerene molecules (2001)
Nairz, Olaf, Arndt, Markus, Zeilinger, Anton
The Heisenberg uncertainty principle for material objects is an essential corner stone of quantum mechanics and clearly visualizes the wave nature of matter. Here we report a demonstration of the...
Entanglement purification for quantum communication (2001)
Jian-Wei Pan, Christoph Simon, Časlav Brukner, Anton Zeilinger
Entanglement of Orbital Angular Momentum States of Photons (2001)
Mair, Alois, Vaziri, Alipasha, Weihs, Gregor, Zeilinger, Anton
So far experimental confirmation of entanglement has been restricted to qubits, i.e. two-state quantum systems including recent realization of three- and four-qubit entanglements. Yet, an ever...
Experimental Four-photon Entanglement and High-fidelity Teleportation (2001)
Pan, Jian-Wei, Daniell, Matthew, Gasparoni, Sara, Weihs, Gregor, Zeilinger, Anton
We experimentally demonstrate observation of highly pure four-photon GHZ entanglement produced by parametric down-conversion and a projective measurement. At the same time this also demonstrates...
Mutually unbiased binary observable sets on N qubits (2001)
Lawrence, Jay, Brukner, Caslav, Zeilinger, Anton
The Pauli operators (tensor products of Pauli matrices) provide a complete basis of operators on the Hilbert space of N qubits. We prove that the set of 4^N-1 Pauli operators may be partitioned into...
Carollo, Angelo, Palma, G. Massimo, Simon, Christoph, Zeilinger, Anton
In a recent paper Bennett et al.[Phys. Rev.A 59, 1070 (1999)] have shown the existence of a basis of product states of a bipartite system with manifest non-local properties. In particular these...
Diffraction of Complex Molecules by Structures Made of Light (2001)
Arndt, Markus, Brezger, Björn, Nairz, Olaf, Zeilinger, Anton
Experimental Demonstration of Four-Photon Entanglement and High-Fidelity Teleportation (2001)
Daniell, Matthew, Gasparoni, Sara, Pan, Jian-Wei, Weihs, Gregor, Zeilinger, Anton
Feasible Entanglement Purification for Quantum Communication (2000)
Pan, Jian-Wei, Simon, Christoph, Brukner, Caslav, Zeilinger, Anton
The distribution of entangled states between distant locations will be essential for the future large scale realization of quantum communication schemes such as quantum cryptography and quantum...
A feasible "Kochen-Specker" experiment with single particles (2000)
Simon, Christoph, Zukowski, Marek, Weinfurter, Harald, Zeilinger, Anton
We present a simple experimental scheme which can be used to demonstrate an all-or-nothing type contradiction between non-contextual hidden variables and quantum mechanics. The scheme, which is...
Quantum Measurement and Shannon Information, A Reply to M. J. W. Hall (2000)
Brukner, Caslav, Zeilinger, Anton
Motivated by Hall's recent comment in quant-ph/0007116 we point out in some detail the essence of our reasoning why we believe that Shannon's information is not an adequate choice when defining the...
Conceptual Inadequacy of the Shannon Information in Quantum Measurements (2000)
Brukner, Caslav, Zeilinger, Anton
In a classical measurement the Shannon information is a natural measure of our ignorance about properties of a system. There, observation removes that ignorance in revealing properties of the system...
Hidden-variable theorems for real experiments (2000)
Simon, Christoph, Brukner, Caslav, Zeilinger, Anton
It has recently been questioned whether the Kochen-Specker theorem is relevant to real experiments, which by necessity only have finite precision. We give an affirmative answer to this question by...
Operationally Invariant Information in Quantum Measurements (2000)
Brukner, Caslav, Zeilinger, Anton
A new measure of information in quantum mechanics is proposed which takes into account that for quantum systems the only feature known before an experiment is performed are the probabilities for...
Quantum Cryptography with Entangled Photons (1999)
Jennewein, Thomas, Simon, Christoph, Weihs, Gregor, WeinfurterD, Harald, Zeilinger, Anton
By realizing a quantum cryptography system based on polarization entangled photon pairs we establish highly secure keys, because a single photon source is approximated and the inherent randomness of...
A Fast and Compact Quantum Random Number Generator (1999)
Jennewein, Thomas, Achleitner, Ulrich, Weihs, Gregor, Weinfurter, Harald, Zeilinger, Anton
We present the realization of a physical quantum random number generator based on the process of splitting a beam of photons on a beam splitter, a quantum mechanical source of true randomness. By...
Optimal Quantum Cloning via Stimulated Emission (1999)
Simon, Christoph, Weihs, Gregor, Zeilinger, Anton
We show that optimal universal quantum cloning can be realized via stimulated emission. Universality of the cloning procedure is achieved by choosing systems that have appropriate symmetries. We...
High-Fidelity Teleportation of Independent Qubits (1999)
Bouwmeester, Dik, Pan, Jian-Wei, Weinfurter, Harald, Zeilinger, Anton
Quantum teleportation is one of the essential primitives of quantum communication. We suggest that any quantum teleportation scheme can be characterized by its efficiency, i.e. how often it succeeds...
Violation of Bell's inequality under strict Einstein locality conditions (1998)
Weihs, Gregor, Jennewein, Thomas, Simon, Christoph, Weinfurter, Harald, Zeilinger, Anton
We observe strong violation of Bell's inequality in an Einstein, Podolsky and Rosen type experiment with independent observers. Our experiment definitely implements the ideas behind the well known...
Observation of three-photon Greenberger-Horne-Zeilinger entanglement (1998)
Bouwmeester, Dik, Pan, Jian-Wei, Daniell, Matthew, Weinfurter, Harald, Zeilinger, Anton
We present the experimental observation of polarization entanglement for three spatially separated photons. Such states of more than two entangled particles, known as GHZ states, play a crucial role...
A posteriori teleportation ? (1998)
Bouwmeester, Dik, Pan, Jian-Wei, Daniell, Matthew, Weinfurter, Harald, Zukowski, Marek, Zeilinger, Anton
Braunstein and Kimble observe correctly that, in the Innsbruck experiment, Nature 390, 575 (1997), one does not always observe a teleported photon conditioned on a coincidence recording at the...
Adriatico Workshop On Quantum Interferometry : 1993 : Trieste, Italy, De Martini, Francesco, Denardo, G. (Gallieno, 1935-, Zeilinger, Anton, International Centre For Theoretical Physics, International Atomic Energy Agency, ...
A la cabeza del título: International Centre for Theoretical Physics, International Atomic Energy Agency, United Nations Educational Scientific and Cultural Organization