Infrastructure

Building for Cryogenic Techniques

System MagLab 2000^*

Under a special project submitted to PRAXIS by ITN and partners at two universities for the upgrade and purchase of new magnetic characterization equipment*, a commercial system (MagLab 2000 from Oxford Instruments) capable of multipurpose characterization measurements at low temperatures and under fields up to 12 T, was acquired. The system comprises a variable temperature insert, operating in the range 1.5-400 K inside a 12 T magnet with a 50 mm bore with several easily interchangeable probes.

• One type of probe allows either magnetisation measurements by an extraction technique or AC-susceptibility measurements.
• Another type of probe, allows specific heat measurements of small samples (~5mg) in the range 2-200 K using a relaxation technique and under different magnetic fields up to 12 T.

All these measurements are, highly automated in a user-friendly environment. These characteristics allow either routine magnetic measurements complementary to those obtained with other techniques, for instance with a SQUID magnetometer, or easy specific heat determinations in small samples.

This equipment, installed at Nuclear and Technological Campus (CTN), is shared with the University of Lisbon and the system is expected to serve different teams of researchers involved in a variety of research projects where the magnetic properties are relevant. The system became recently operational having already a long waiting list of experiments of benefit to research projects involving teams at CTN, FCUL, University of Coimbra or IST in different subjects such as:

• Magnetic phase transitions in Intermetallics
• Heavy Fermion systems
• Molecular Conductors
• Molecular magnets
• Magnetic oxides and magnetic particles