We report on the generation of a continuous variable Einstein-Podolsky-Rosen (EPR) entanglement using an optical fibre interferometer. The Kerr nonlinearity in the fibre is exploited for the generation of two independent squeezed beams. These interfere at a beam splitter and EPR entanglement is obtained between the output beams. The correlation of the amplitude (phase) quadratures are measured to be 4.0 ± 0.2 (4.0 ± 0.4) dB below the quantum noise limit. The sum criterion for these squeezing variances 0.80 ± 0.03 < 2 verifies the nonseparability of the state. The product of the inferred uncertainties for one beam (0.64 ± 0.08) is well below the EPR limit of unity.Since the original proposal of a Gedankenexperiment intending to show the incompleteness of quantum mechanics in 1935 [1], a number of schemes for generating the Einstein-Podolsky-Rosen (EPR) entanglement have been realized. The schemes range from the production of gamma-ray pairs from positron-electron annihilations [2], to proton pairs [3], to pairs of low-energy photons from atomic radiative cascade [4] and more recently to schemes involving optical parametric processes [5]. Most of these initial experiments utilized the entanglement as originally intended: to test the validity of quantum mechanics via either the violation of Bell inequality [4] or the demonstration of the EPR paradox [6]. Following the proposals of a myriad of quantum information schemes in recent years where entanglement is regarded as a basic requisite, the subject matter has experienced a resurgence of interest. The purposes of entanglement generation are now shifting to that of quantum information applications. Amongst these applications are the realization of quantum teleportation, the implementation of dense coding, quantum cryptography and other quantum communication schemes [7]. In view of these changing needs, it is desirable to explore simpler and more reliable alternatives for the generation of EPR entanglement.In this letter, we report on what is to our knowledge the first generation of EPR entanglement of photons that does not rely on any pair production process, such as those in the above-mentioned examples. Instead, the Kerr (χ (3) ) nonlinearity of an optical fibre is utilized to produce two amplitude squeezed beams, with the nonlinear interaction on each beam uncoupled to the other. To create the EPR entanglement, no additional nonlinear interaction is required. Instead, the amplitude squeezed beams are made to interfere at a 50/50 beam splitter [8]. In this vein sum squeezing is obtained for the amplitude quadratures and difference squeezing for the phase quadratures. The signs of these correlations are interchanged compared to those achieved in other systems. This fact may be of importance in applications involving the opto-mechanical coupling of radiation pressure [9]. Apart from the simplicity of our scheme, it also has the potential advantage of being integrable into existing fibre-optics communication networks.

CAD/CAM milling systems provide a rapid and individual method for the manufacturing of zirconia dental restorations. However, the disadvantages of these systems include limited accuracy, possible introduction of microscopic cracks, and a waste of material due to the principle of the 'subtractive process'. The hypothesis of this study was that these issues can be overcome by a novel generative manufacturing technique, direct inkjet printing. A tailored zirconia-based ceramic suspension with 27 vol% solid content was synthesized. The suspension was printed on a conventional, but modified, drop-on-demand inkjet printer. A cleaning unit and a drying device allowed for the build-up of dense components of the size of a posterior crown. A characteristic strength of 763 MPa and a mean fracture toughness of 6.7 MPam(0.5) were determined on 3D-printed and subsequently sintered specimens. The novel technique has great potential to produce, cost-efficiently, all-ceramic dental restorations at high accuracy and with a minimum of materials consumption.

Drying and sintering of conductive nanoparticle inks for printed electronics attracts more and more interest. Sintering can be performed not only by conventional thermal heating (e.g. using a hot plate or an oven), but also by alternative sintering methods such as microwave, laser, intense pulsed light (IPL) sintering and others. It was recognized that most of the sintering processes limit the feasibility of roll-to-roll (R2R) processing due to the long time duration required for the sintering. In this contribution, we report about R2R IR drying and sintering of inkjet-printed silver (Ag) layers on a non-absorbent polyethylene naphthalate (PEN) substrate. A tailored IR module was developed and installed in a R2R printing system. We demonstrated the high potential of the IR post-treatment technology resulting in a conductivity of up to 15% of that of bulk Ag. In comparison to a conventional hot plate drying and sintering the conductivity achieved using the IR approach was more than doubled. By optimization of the presented IR parameters, drying and sintering was achieved at high web velocities up to 1 m s−1 with an exposure time of less than 0.5 s