EXTREM · Condensed matter research at extreme experimental conditions

Final Activity Report Summary - EXTREM (Condensed Matter Research at Extreme Experimental Conditions)

Objective 1. Construction of a small-sized 3He-4He dilution refrigerator. The constructed refrigerator achieves 28 mK with a superconducting coil of 10 Tesla maximal field. The transport measurement and the relaxation technique for heat capacity studies are installed. The special rotator enables investigations of anisotropic properties of the crystals of interest as well a formation of the point contacts in milikelvins. The rotator has been designed with the knowledge obtained from UAM at the design and construction of the low temperature scanning tunnelling microscope. The unique skills have been obtained by many of our people from Dr Karl Neumaier, the world specialist in the design and construction of the dilution refrigerators. The main part of TOK went to Dr S. Gabani and ing. Emil Gazo, the young permanent researchers at CLTP, who performed the overall construction of the refrigerator in Kosice and learned many details. Also Ing. M. Medeova obtained intensive training in construction of the special resistance bridge for milikelvins. Objective 2. Development of ultra sensitive calorimetry. The ac microcalorimetry has been completed and installed in the special insert working in the 4He temperature range and in another modification also in the helium-3 refrigerator. Recently our calorimeter is working at even lower temperatures than in CEA Grenoble from where all the details on this special technique were learnt. Dr C. Marcenat from CEA was the person who taught Dr K. Kacmarcik and Dr Z. Pribulova all secrets but many others participated in the courses. Objective 3. High pressure measurements. The planned achievements have been considerable overcome. In the original plan we wanted to learn on the technique and obtain scientific results measuring on the installation in CEA. But a part of this the whole new diamond anvil pressure cell has been constructed for use in Kosice. The important issue is that it was done in the same way as all other objectives - via learning by doing. This time Dr. S. Gabani designed the pressure cell under supervision of Dr. D. Braithwaite, a world known expert in the field. Also Dr. Flachbart, the senior researcher at CLTP has learned many details in the technique and obtained important practise in the measurements. 4. Improvement of scanning tunnelling spectroscopy. Again in this objective we have not stop at improvements of our previous technique (the point contact spectroscopy in this case), but the whole scanning tunnelling microscope has been designed, constructed and tested for work in the milikelvin range. Mainly, Dr Pavol Szabo obtained all knowledge on the construction of STM heads and a use of the STM controler. TOK has been delivered by prof. J.G. Rodrigo from UAM Madrid. The success of TOK can be documented by the fact that the second STM head, recently working in the helium-3 refrigerator, has been completely done in Kosice by Dr Szabo and Dr Komanicky. Dr Komanicky, originating from the Argonne national laboratory was the third recruited person in the project and he contributed to the construction of the dilution fridge as well as of the STM system. After finishing this TOK project he became a permanent in CLTP where he will continue in further development of the unique techniques. Dr. P. Samuely has also profited a lot from TOK concerning many details of the STM techniques. It is very important that all the main people listed above who obtain a major TOK in the special techniques continue their engagements in CLTP either on permanent positions or tenure tracks. Among those researchers we have two female ones - Dr Zuzana Pribulova and Ing. M. Medeova. Many other colleagues, postdocs and students have also profited from TOK being involved in "'learning by doing" or participated in many courses organised within the project and led by the recruited researchers. It is worth noticing that engineers from the industrial company have participated in the course on cryogenics organised within the project.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз