QUROPE Quantum Information Processing and Communication in Europe

We are happy to announce that, by decision of the QUIE2T Advisory Board of Experts and upon approval by the QUIE2T Coordination Steering committee, the

2013 European Quantum Information Young Investigator Award

has been awarded jointly to

We have investigated the microwave frequency dynamic admittance of a quantum dot tunnel coupled to a two-dimensional electron gas. The measurements are made via a high-quality 6.75 GHz on-chip resonator capacitively coupled to the dot. The resonator frequency is found to shift both down and up close to conductance resonances of the dot corresponding to a change in the reactance of the system from capacitive to inductive (see Fig. 1). The observations are consistently explained in a scattering matrix model.

One important key characteristics of a non-classical physical system is entanglement. For a system containing three qubits two important classes of entangled states are GHZ- and W-states. The first class consists of superposition states between |000⟩ and |111⟩ and the second one arises when a single excitation is symmetrically shared between three qubits, i.e. in an equal superposition between |001⟩, |010⟩ and |100⟩.

Tomography is the main method used for measuring the fidelity of an experimentally implemented quantum process. However, it is a very inefficient method since the number of measurements as well as the time needed for the data post-processing scale exponentially with the number of qubits. With the ongoing experimental progress and growth in system size, quantum process tomography will soon become infeasible in state-of-the art experiments.

You can get a free copy here: http://physicsworld.com/cws/download/mar2013

The New York Times writes about quantum computers.

As its last last deliverable, QUIE2T WP2 has submitted the final updates of the QIPC Strategic Report (v. 1.8) and the Quantum Information Classification scheme QICS (v. 1.3). A detailed report on the update is available from the WP2 deliverables page (deliverable D2.2.2).

Scientists from the Kavli Institute of Nanoscience have brought two atomic nuclei in synthetic diamond into a quantum entangled state. They published their findings on 14 October 2012 online in Nature Physics.

Demonstration of entanglement-by-measurement of solid state qubits
W. Pfaff, T.H. Taminiau, L. Robledo, H. Bernien, M.L. Markham, D. J. Twitchen, R. Hanson
Nature Physics 9, 29–33 (2013)

Researchers from the Kavli Institute of Nanoscience (Delft University of Technology) and the FOM Foundation have devised a new method for reading out the electron state in a carbon nanotube. They did this by 'stamping’ an individual nanotube on a chip. Then the electron state can be read out, as the nanotube remains very clean and controllable. Electrons in such a nanotube can acquire special quantum characteristics which make these structures interesting for future quantum computers. The readout of the electron states is a crucial step in this.

A slide show of the (QUIE2T sponsored) ICAP round table is now available on-line, follow the link below.