On the molecular, scale magnet interactions can have powerful effects both in biological and electrical systems. However, when it comes to measuring magnetism on a nanoscopic scale, past methods have come up short. For this reason, one of the most important physical phenomena that may affect the behavior of recent nanoinventions is poorly understood.
A new method may change that. Researchers with the Rensselaer Polytechnic Institute have developed the first accurate way of measuring nanoscopic magnetism.
The new process involves inserting cobalt nanoclusters between 1 nm and 10 nm into a single multi-walled carbon nanotube. As the carbon nanotube is an excellent conductor, it is also sensitive to magnetic activity, such as that of the cobalt nanoclusters. The result is a magnetic nanomaterial, which also can sense electrically other magnetic nanofields.
Swastik Kar, research assistant professor in Rensselaer’s Department of Physics, Applied Physics, & Astronomy, who led the project explains the key to unlocking this mystery, stating, "Since the cobalt clusters in our system are embedded inside the nanotube rather than on the surface, they do not cause electron scattering and thus do not seem to impact the attractive conductive properties of the host carbon nanotube. Since the cobalt clusters in our system are embedded inside the nanotube rather than on the surface, they do not cause electron scattering and thus do not seem to impact the attractive conductive properties of the host carbon nanotube."
Saroj Nayak, an associate professor in Rensselaer’s Department of Department of Physics, Applied Physics, and Astronomy, who also contributed to the project, goes on to talk about future applications stating, "These novel hybrid nanostructures open up new avenues of research in fundamental and applied physics, and pave the way for increased functionality in carbon nanotube electronics utilizing the magnetic degree of freedom that could give rise to important spintronics applications."
Just a few of potential applications -- new ultra-precise drug delivery systems, tiny conductance sensors, nanotube-based memory, and spintronic materials. Spintronics is a field of quantum computing which seeks to program electrons with information by changing their spin. This is a hot research field today.
A paper on the study appears in the journal Nano Letters.
Other authors on the paper include Caterina Soldano, formerly a graduate student at Rensselaer who is now a postdoctoral research associate at the Centre d’Elaboration de Matériaux et d’Etudes Structurales in Tolouse, France; Professor Saikat Talapatra of the Physics Department of Southern Illinois University, Carbondale; and Prof. P.M. Ajayan of the Rice University Department of Mechanical Engineering and Materials Science.
The research was funded by the New York State Interconnect Focus Center at Rensselaer.