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�This discovery sharpens our understanding of what,
literally, holds the world together and brings physicists one step
closer to getting a grip on superconductivity at high temperatures.
Until now, physicists were going around in circles, so this discovery
will help to drive new understanding,� said Prof. Bianchi, who was
recruited to UdeM as a Canada Research Chair in Novel Materials for
Spintronics last fall and performed his experiments at the Paul
Scherrer Institute in Switzerland, in collaboration with scientists
from ETH Zurich, the University of Notre Dame, the University of
Birmingham, U.K., the Los Alamos National Laboratory and the
Brookhaven National Laboratory.
Magnetic tornado that grows stronger
Using the Swiss Spallation Neutron Source (SINQ),
Prof. Bianchi and his team cooled a single-crystal sample of CeCoIn5
down to 50mK above absolute zero and applied a magnetic field nearly
high enough to entirely suppress superconductivity. They found that
the core of the vortices feature electronic spins that are partly
aligned with the magnetic field. This is the first experimental
evidence that a theory that describes the properties of
superconducting vortices and, for which Abrikosov and Ginzburg
received the Nobel Prize in 2003, which does not generally apply in
magnetically-induced superconductors.
�When subjected to intense magnetic fields, these
materials produce a completely new type of magnetic tornado that grows
stronger with increasing fields rather than weakening,� said Prof.
Bianchi. �The beauty of this compound is how we can experiment without
breaking it.�
Superconductors hold great promise for
technological applications that will change how modern civilization
can store and transmit energy - arguably some of the most pressing
challenges today. Other notable applications include superconducting
digital filters for high-speed communications, more efficient and
reliable generators and motors, and superconducting device
applications in medical magnetic resonance imaging machines. The first
superconductor was discovered nearly a hundred years ago, and in most
materials this curious state with no resistance was shown to arise
from the interaction of the electrons with the crystal; however, in
this new material, superconductivity is thought to arise from magnetic
interactions between electrons.
About the Universit� de Montr�al
Deeply rooted in Montreal and dedicated to its
international mission, the Universit� de Montr�al is one of the top
universities in the French-speaking world. Founded in 1878, the
Universit� de Montr�al today has 13 faculties and together with its
two affiliated schools, the HEC Montr�al and �cole Polytechnique,
constitutes the largest centre of higher education and research in
Qu�bec, the second largest in Canada, and one of the major centres in
North America. It brings together 2,400 professors and researchers,
accommodates more than 55,000 students, offers some 650 programs at
all academic levels, and awards about 3,000 masters and doctorate
diplomas each year.
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