Magnetism and Low Temperatures Laboratories (MLTL) are situated on the grounds of the Faculty of Mathematics and Physics of the Charles University in Prague (FMP CUP) in the Building “C” (Fig. on the left) in the Campus Troja and are operated by the Department of Condensed Matter Physics in cooperation with the Department of Low Temperature Physics.
The Building “C” is completely equipped for operating modern experimental facilities dedicated for the study of physical properties of novel materials at low temperatures and high magnetic fields. An essential part of the building is the up to date facility for production, storage and supply of cryogenic liquids with a Helium liquefier CE1410 (Figure on the right) delivered by Linde. This modern high capacity equipment is capable of producing more than 30 litres of liquid He hourly and supply it to cryogenic and cryomagnetic devices in the MLTL, as well as to all the other low-temperature laboratories within FMP CUP. Due to this conception the Building “C” became a natural environment for creation of an important Czech research infrastructure offering significant feasibility of the investigation of materials at low temperatures and in high magnetic fields, which is included in the Roadmap for Large Research, Development and Innovation Infrastructures in the Czech Republic.
MLTL is presently financially supported within the program of Czech Research Infrastructures (project no. LM2011025).
Step by step there have been installed and put into operation a series of unique cryomagnetic devices, which are being continuously upgraded with the goal of reaching large variability of external parameters for investigation of novel materials under multi-extreme conditions (low temperatures, high magnetic fields and high external pressures). These instruments now offer highly accurate and highly effective measurements of magnetic, transport, thermal and cohesive properties of materials and other physical phenomena in the wide temperature range from 30 mK up to 1000 K, in magnetic fields up to 14 T and in external pressures up to 12 GPa. These precise measurements can be performed on miniature samples. Such extraordinary conditions can MLTL offer due to installation of PPMS9T, PPMS14T and MPMS7T apparatuses (following picture - positions A, B, D, respectively) provided by Quantum Design and implementing in them several novel measurement options. The 9 T cryomagnet from Cryomagnetics Inc. (following picture, position C) with a 3He/4He dilution refrigerator provided by Leiden Cryogenics (see 9T&30mK) has been so far equipped for measurements of the specific heat, electrical resistance and AC susceptibility in magnetic fields up to 9 T at temperatures down of 30 mK and external pressures so far up to 3 GPa. The instrument 9T&30mK will be step by step upgraded by implementing further experimental options.
A substantial upgrade of MLTL facilities provides a Cryomagnet from Cryogenics Ltd. with a maximum magnetic field of 20 T complemented by a gradient coil. The instrument 20T&30mK based on the 20 T Cryomagnet will also enable use of the 3He/4He dilution refrigerator and finally will offer the entire variety of measuring methods presently available in MLTL.
Further important upgrade of MLTL facilities is provided by the dedicated Low Temperature Diffractometer (LT Diffractometer) equipped by a closed cycle refrigerator enabling powder diffraction measurements at temperatures 4 – 300 K.
PPMS9T and PPMS14T instruments have been jointly acquired by FMP CUP and the Institute of Physics ASCR around 2000 and are operated within the frame of Joint Laboratory of Magnetic Studies.
The main mission of MLTL is to provide broad scientific community unique possibilities for comprehensive experimental studies of physical phenomena and properties of materials in multiextreme conditions – low temperatures, high magnetic fields and high external pressures - including controlled preparation and characterization of the samples studied in the associated materials technology laboratories. The main strategic objective is the excellence of the infrastructure on the international scale.
Open Access to MLTL facilities
MLTL offer access for external users to its cryomagnetic facilities dedicated to measurements of a rich spectrum of physical properties of materials in various conditions (wide range of temperatures, magnetic fields and hydrostatic and uniaxial pressures) and to the associated technology facilities enabling controlled preparation and characterization of high quality samples (single crystals and also polycrystals) of materials of various types to those who cannot come with their own well characterized samples for experiments. The range of facilities offering open access will be extended in reaction to user’s requests.
Access to the facilities is free of charge for national and international academic users, provided that the results from experiments at the MLTL facilities will be disseminated in the public domain with an adequate reference to the infrastructure. There is also a limited possibility of providing financial support of living expenses of users coming for an experiment from institutions outside Prague.
To apply for access to the MLTL infrastructure facilities, scientific proposals should be submitted via User portal. There are no deadlines; the proposals can be submitted at any time. The proposals for experiments are evaluated on the fly by the MLTL Panel on the basis of scientific excellence and considering needs of students for bachelor, master and doctoral thesis. An adequate experimental time will be allocated to the accepted proposals and the experiment will be scheduled in concert with user needs , taking into account the possibilities of the laboratory.