Final Report Summary - CIPRIS (Coherent Information Processing in Rare-earth Ion doped Solids) The scientific work program of CIPRIS aimed at the successful implementations of rare-earth doped media, in particular towards applications for future information technology. Particular goals were developments of novel information processors, driven by coherent interactions between radiation fields and rare-earth ion doped solids. CIPRIS followed two scientific approaches : Classical processing and quantum processing. Both were meant as pronounced inter-disciplinary research efforts, combining physics, material science and information technology. To achieve the aims, CIPRIS defined four work packages (WPs). These dealt with the following subjects : (WP1) Crystal growth and spectroscopy of rare-earth ion doped solids. (WP2) Optical and RF control in rare-earth ion doped solids. (WP3) Classical storage/processing in rare-earth ion doped solids. (WP4) Quantum storage/processing in rare-earth ion doped solids.The goal of CIPRIS in terms of training was the development of the next generation of young researchers with appropriate skills to exploit the concepts of rare-earth-based information technology, pushing it towards commercial applications. This contributes to a European knowledge base for future information technology. The specific scientific objectives of CIPRIS in the reporting period, as defined by scientific deliverables/tasks due to M48 were : (D1.1) Samples and publication of growth and spectroscopy of rare-earth ion doped solids (oxides) with large coherence time and oscillator strength for quantum storage/processing. (D1.2) Samples and publication of growth and spectroscopy of an Erbium doped crystal with large inhomogeneous linewidth for classical storage/processing. (D1.3) Samples and publication of growth and spectroscopy of rare-earth ion doped solids (fluorides) for quantum storage and processing. (D1.4) Samples and publication of growth and spectroscopy of Erbium-doped multi-site or disordered fluoride crystals for classical storage and processing. (D2.1) Publication on implementation of feedback-controlled pulse shaping for light storage in rare-earth ion doped solids. (D2.2) Publication on implementation of decoherence control to prolong storage times (e.g. of images) in rare-earth ion doped solids. (D2.3) Publication on determination of parameters forthe ZEFOZ point in rare-earth ion doped solids. (D3.1) Report on determination of the limitations of a rare-earth RF processor in industry environment. (D3.2) Demonstration device of an Erbium-based rare-earth processor with large bandwidth. (D3.3) Publication on implementation of image storage and/or classical optical logic operations in rare-earth ion doped solids. (D3.4) Publication on demonstration of a spectral and/or temporal sideband filter in rare-earth ion doped solids. (D4.1) Publication on high-fidelity quantum gate operations for rare-earth ion doped solids. (D4.2) Publication on detecting the quantum state of an individual ion in a rare-earth ion doped solids. (D4.3) Publication on demonstration of on-demand atomic frequency comb quantum memory in the millisecond regime using spin control. (D4.4) Publication on storage of light at the single photon level in an atomic frequency comb memory using spin waves. (D4.5) Publication on development of a rare-earth ion doped solid quantum memory with coherence times well beyond one second.The specific objectives of CIPRIS with regard to training up to M48 were : (i) Recruitment and training of 9 early-stage researchers and 4 experienced researchers on CIPRIS-related scientific projects. (ii) Three mini-schools, dealing with “Light-matter interactions”, “Crystal growth and spectroscopy”, and “Rare-earth information processing”. (iii) Two laboratory courses on “Radio-frequency excitations in doped crystals” and “Crystal growth and characterization”. (iv) Final conference on information processing in solids. (v) Soft-skill seminar, attached to the first mini school. (vi) Career planning session, attached to the final conference. (vii) Industry seminar.The research and training program of CIPRIS proceeded as initially planned. The partners worked on the implementation of experimental setups, performed successful experiments, and collected data, which lead to 71 papers with relevance to CIPRIS in scientific journals (published, in press or submitted), specific rare-earth crystal samples, and a demonstration device of an Erbium-based rare-earth processor with commercial relevance. This large number of publications and other research results mirrors the significant scientific output of CIPRIS. For a full publication list and PDFs see www.cipris.eu.CIPRIS fully achieved the vast majority of scientific deliverables, many of them with far more scientific output than initially expected. In few exceptions the deliverable is partially fulfilled, but even in these cases with considerable scientific output already, e.g. in terms of publications. The vast majority of relevant experimental data and developments are already published by now by the CIPRIS partners. Very few scientific papers are still in press or about to be submitted (based on successfully completed measurements and available convincing experimental data). Beyond publications, the successful tasks also include delivery of crystal samples and significant progress towards a demonstration device.Among the scientific deliverables, CIPRIS lead to a large number of important results and developments, which were published in high-impact journals, triggering significant feedback from the scientific community as well as the interested public. We highlight now only the most prominent results, selecting one from each work package : In WP1, CNRS-LCMCP grew isotopically pure Europium-doped crystals and delivered them to UNIGE and TUDA for applications in quantum memories. Such isotopically pure crystals are commercially not available. They are required for high-efficiency quantum memories, enabling storage durations of hours or even days. In WP2, TUDA published world-record data on stopping and storage of light pulses for up to one minute. The work lead to a huge feedback from general media worldwide (for details see outreach in section “Dissemination activities” below). It was also selected by the American Physical Society in “Physics” as one of the 10 major research highlights in world-wide physics 2013. In an extension of the project, TUDA recently also demonstrated a world-record storage efficiency in the rare-earth doped solid. In WP3, CNRS-LAC and the industry partner TRT setup a demonstration device for opto-RF signal processing in a doped solid. This exhibits a big step forward towards commercial applications of rare-earth data processing. In WP4, ICFO stored a photonic qubit in a doped solid quantum memory. This is a key experiment for quantum information technology. The results attracted considerable interest in the scientific community and beyond.In summary, CIPRIS implemented numerous successful demonstrations of information processing in rare-earth doped media, yielding large impact in the scientific community. In terms of applications, the combination of rare-earth doped crystals and light-matter interactions exhibits a promising approach towards realistic implementations of future information technologies. CIPRIS significantly drove this emerging technology forward. CIPRIS also successfully implemented its central goal in terms of training, i.e. the development of the next generation of young researchers with appropriate skills to exploit the concepts of rare-earth-based information technology – pushing it towards commercial applications. This contributes to a European knowledge base for a future information technology.
