Project

Magnetism; Physics; Spintronics; Magnetization; SQUID; low-temperature; magnetometer; hysteresis; coercivity

Lead
Lay summary
Magnetization measurements is the cornerstone of research in magnetic materials, from complex quantum magnetism to high-tech materials science. This project establlishes a state of the art SQUID magnetometer combined with a 3He cooling system, a high-temperature oven and a pressure cell. It will allow fast and reliable measurements over 3 orders of magnitude in temperature range from 0.3K to 700K, and measurements under high pressures to 10kbar, both with hitherto unprecedented sensitivity. The facility will serve a broad userbase within EPFL and we are open to requests from anywhere in Switzerland

Direct link to Lay Summary

Last update: 21.02.2013

Number	Title	Start	Funding scheme

The study of magnetism in materials remains at the forefront of contemporary condensed matter physics. It ranges from the study of fundamental collective quantum effects, through novel electronic properties in emerging materials to the technologically inspired field of spintronics. Common to all of these fields is that the most fundamental quantity that can be measured is the magnetization, and how it develops with temperature, applied magnetic field and varying sample parameters. Essentially, it is the prerequisite to any other investigations.Here we propose to acquire a state of the art SQUID magnetometer combined with a 3He cooling system, a high-temperature oven and a pressure cell. It will allow fast and reliable measurements over 3 orders of magnitude in temperature range from 0.4K to 800K, and measurements under high pressures to 10kbar, both with hitherto unprecedented sensitivity. There exist in Europe only one other SQUID magnetometer with the 0.4K option included in this request.The applicant’s Laboratory for Quantum Magnetism (LQM) studies materials displaying fundamental collective quantum phenomena using the combination of neutron scattering techniques and laboratory-based bulk measurements. The activities span from new materials discovery to unraveling the fundamentals of quantum physics and the enigma of correlated electron superconductivity. Essentially all projects in the laboratory (of which selected specific examples are outlined in section 2) require access to accurate magnetization measurements, and a significant fraction of the projects requires measurements to temperatures below 2 Kelvin. The requested SQUID magnetometer will boost research within the laboratory, provide an advantage towards competing labs in other countries, and be a source for new collaborations and projects.The co-applicant’s Laboratory of the Physics of Nanostructured Materials (LPMN) studies spintronics - i.e. devices exploiting coupled electronic and magnetic states of electrons - the most notable example being the Nobel-rewarded giant-magneto- resistance now used in hard-disks. Complementing the transport measurements on in-house fabricated samples, it is of outmost importance to characterize the magnetic properties. No equipment is currently available with sufficient sensitivity to measure magnetization of the nano-structured materials. The requested SQUID magnetometer will be an invaluable addition to the laboratory’s research.The equipment will be a facility open to users and collaborators from EPFL, Switzerland and internationally. Specifically, the scientific case includes sub-projects from collaborators at Uni. Bern, ETH-Zürich and PSI, and intentions of use have been expressed by groups in the Institute of Chemistry, the Institute of Materials and the Institute of Micro-Engineering, and even from Swiss industry.