Photoemission spectroscopy
link to Dr. Grioni activities.
Growing Unique Crystals for Research
The laboratory for crystal growth in Lausanne plays a very special role within MANEP. It produces a wide variety of high-quality single crystals that are used for research programs by groups throughout the world, including several MANEP members. In many cases, the laboratory is the only available supplier of the material, and as such its products are in very high demand.
The growth of high-quality single crystals is a sophisticated scientific enterprise with some magic-touch overtones. The head of the laboratory, Helmuth Berger, has worked for more than 30 years in this highly specialized domain that supports the research activities of many of his colleagues. The best known specialty of the laboratory is the growth of low-dimensional crystals. The most famous at present are of course layered high-temperature superconductors.
The laboratory grows a variety of materials in this family, including pure and doped BCSCO with a variety of dopants such as Pb, Pr, Dy, Y etc., as well as YBCO-based specimens. The production of layered crystals goes well beyond high-temperature superconductors and includes many other families such as II-V compounds, chalcogenides, iodides, chlorides and organic materials. Quasi-one-dimensional crystals are also widely produced, including transition metal selenides or sulphides. The quality of such crystals is so high that they can be used for the most demanding experiments, such as studies of non-Fermi-liquid behavior by high-resolution photoemission. Although famous worldwide for its low-dimensional crystals, the laboratory also produces other types of specimens. For example, it was recently able to obtain unique crystals of transition metal oxides (anatase) as well as very large high-quality single crystals of fullerenes.
These examples cover a small part of the production. The laboratory continuously explores the growth of novel materials, and new results are obtained almost every week. In many cases, the new growth projects are performed in collaboration with future users and respond to their specific requirements. Quite often, on the other hand, the laboratory produces novel materials on its own, opening new avenues for research. The stock of materials includes several hundreds different compounds, and constitutes a precious resource which is made available on demand to researchers throughout Europe and beyond.
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