European researchers have introduced a graphene-based device to identify minute magnetic fields with an excellent sensitivity as low as the stray field of some magnetic molecules.
The team deposited magnetic molecules on a graphene sheet, a one atom-thick layer of carbon exhibiting peculiar properties. They used graphene as a spider’s web to chemically engulf molecules and to analyze their magnetization properties simultaneously by capturing their magnetic flux and generating related electrical signal. They created molecules suited for embedding in the graphene honeycomb lattice. Then they modified the graphene sheet to form a device of size 10 nm. At last electrical measurements was carried out at very low temperatures to reduce the device noise. This advancement in spintronics will pave the way for molecular sensors and ultra, high density storage memories.
Nano Letters journal has published this research work. The scientists from the S3 Center of Istituto Nanoscienze–Cnr, the Karlsruhe Institute of Technology and the Insitut Néel – CNRS, worked with this study.
Spintronics uses magnetic molecules also called nano-magnets measuring few billionth of a meter, because they are capable of storing a bit of data in very less volume. It is critical to be able to ‘read’ miniature units that may grow to molecular size in order to create new future models of magnetic memories.
This ultra-sensitive product allows magnetic reading at the molecular level. Andrea Candini, researcher at the Istituto Nanoscienze-Cnr stated that detection of such minute objects was not possible previously and to be more precise, the past record of sensitivity has been beaten by a factor of 100.
As per the research, graphene combined with magnetic molecules can be used to store data because the device is identical to the spin valve in the reading head of present day hard disks except that it is much smaller, she added. Also this device will enable detection of bio-molecules engineered with a single magnetic molecule like ultra-sensitive sensors incorporated in a lab-on-a-chip.