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37th European Photovoltaic Solar Energy Conference and Exhibition; 228-232, For the current PV production about 2000 tons of silver are consumed per year. This is already 10% of the entire world annual silver supply. The PV production is expected to grow significantly in the next decades in order to enable the energy transition to 100% renewables. Annual production volumes in the terawatt range are predicted already for 2030 and this may lead to higher silver price and put more pressure on the industry to replace silver by copper. With the currently available processes the cost advantage of copper plating over screen printing is relatively small and the implementation of plating in production is slowed down by the high up-front investment for equipment. The highest cost share of the process sequence has the patterning and research activities focus on new, i.e. more cost competitive patterning techniques. Within the Ameliz project several approaches are investigated: firstly, patterning by printing a metal seed grid with a dielectric layer as plating mask and secondly masking by a monolayer of self-assembling molecules. These molecules consist of a phosphonic acid group and a hydrocarbon chain. They are bonded to the ITO surface and form a monolayer of well-ordered, densely packed hydrophobic chains, which protects the ITO surface against plating solutions. Furthermore, methods for selective formation of a copper seed layer by electrografting and for improved adhesion by ITO reduction are being investigated.

36th European Photovoltaic Solar Energy Conference and Exhibition; 677-678, Aluminum zinc oxide is chemically very sensitive and wet processing solutions have to be carefully chosen. We present a process sequence for electrodeposition of copper on solar cells, originally developed for heterojunction cells with indium thin oxide and modified for solar cells with aluminum zinc oxide. The process comprises a sputtered seed layer and patterning by hotmelt inkjet printing. High efficiency above 24.7% and excellent reliability have been demonstrated on heterojunction cells with ITO, good fill factor achieved on c-Si cells with poly-Si carrier selective contacts with AZO and the process has been demonstrated on industrial CIGS substrates.

We report on the observation of the strong-coupling regime between quantum well excitons and a high incidence “Brewster cavity mode” previously identified as the generalized Brewster angle condition in multilayer structures [H. F. Mahlein, J. Opt. Soc. Am. 64, 647 (1974)]. This propagating mode is inside the light cone and therefore can be accessed from the top side of the sample without the need for prism or grating coupling methods. The observed anticrossing is clear evidence of the strong light-matter coupling regime. All the results are accurately reproduced by transfer matrix simulations. These results demonstrate the high potential of such structures for the study of propagating polaritons at high k, which could be harnessed for the realization of polaritonic circuit devices.

Dynamic cardiomyoplasty is a therapeutic possibility in irreversible cardiac insufficiency. With this operation, the latissimus dorsi muscle is mobilised and drawn into the thorax where it is placed around the heart. Lateral and supine positioning as well as thoracotomy and direct manipulation of the heart are associated with particular risks during surgery. Eight patients with the diagnosis of cardiomyopathy underwent cardiomyoplasty. The patients were classified as NYHA III-IV. Continuous dobutamine infusions were routinely started after induction of anaesthesia. All patients were intubated with single-lumen tubes. After sternotomy, lidocaine was administered. Monitoring included Swan-Ganz catheterisation and invasive blood pressure measurement. With early use of inotropic and vasodilatator agents the cardiac index and peripheral vascular resistance were adequately maintained. Double-lumen intubation seems to be unnecessary during cardiomyoplasty and only increases patient risk. Prophylactic lidocaine infusions are effective in preventing ventricular tachycardia and fibrillation. We conclude that adequate intraoperative management can improve the haemodynamic status of these patients so that cardiomyoplasty may be performed without significant morbidity.

Best Paper Award.; International audience; Since their prediction in 1996, non-equilibrium polariton condensates have attracted a lot of interest, as they should allow for the realization of ultralow threshold coherent light-emitters [1]. However, the steep dispersion and the short radiative lifetime of lower polaritons (LP) within the light cone hinder their relaxation toward the center of the Brillouin zone, limiting the polariton lasing threshold. Experimental studies carried out on GaAs and CdTe-based microcavities however revealed that one available channel to bypass efficiently the relaxation bottleneck was the relaxation of LPs from the excitonic reservoir directly to the ground state of the LP branch (LPB) through the emission of one LO-phonon [2]. Here, we study by non-resonant angle- and time-resolved photoluminescence experiments the LP relaxation dynamics in a GaN-based multi-quantum well microcavity, for which polariton condensation has been reported between 10 and 340 K [3]. Regarding the strong Fröhlich interaction in GaN, we particularly investigate the role of LO-phonon on the overall LP relaxation mechanism. We first show that LPs efficiently bind into cavity biexcitons and we demonstrate that the latter complexes are in thermal equilibrium with the excitonic reservoir. We then not only demonstrate the existence of a LO-phonon enhanced relaxation channel from the excitonic reservoir toward the ground state, but also the direct feeding of the LPB by the radiative dissociation of cavity biexcitons mediated by one LO-phonon. In other words, when the energy of the bottom of the LPB corresponds to that of the first LO-phonon replica of the cavity biexciton, we observe an enhanced scattering of polaritons toward the k// = 0 state, as well as a decrease in the condensation threshold. This peculiar observation indicates that the LO-phonon assisted dissociation of excitonic molecules constitutes an additional and efficient relaxation channel driving the condensation threshold of polaritons [4]. A. Imamoglŭ et al., Phys. Rev. A 53, 4250 (1996). see for instance F. Boeuf et al., Phys. Rev. B 62, R2279 (2000). J. Levrat et al., Phys. Rev. B 81, 125305 (2010). P. Corfdir et al., submitted to Phys. Rev. B (2012).