R&D: Graphene Overcoats for Ultra-High Storage Density Magnetic Media

Nature Communications has published an article written by N. Dwivedi, CSIR-Advanced Materials and Processes Research Institute, Bhopal, India, and Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore, A. K. Ott, Cambridge Graphene Centre, University of Cambridge, Cambridge, UK, and Department of Engineering, University of Exeter, Exeter, UK, K. Sasikumar, Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL, USA, C. Dou, Cambridge Graphene Centre, University of Cambridge, Cambridge, UK, R. J. Yeo, Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore, and Institute of Materials, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland, B. Narayanan, Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL, USA , U. Sassi, D. De Fazio, G. Soavi, Cambridge Graphene Centre, University of Cambridge, Cambridge, UK, T. Dutta, Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore, and Empa-Swiss Federal Laboratories for Material Science and Technology, Dübendorf, Switzerland, O. Balci, S. Shinde, J. Zhang, A. K. Katiyar, Cambridge Graphene Centre, University of Cambridge, Cambridge, UK, P. S. Keatley, Department of Physics and Astronomy, University of Exeter, Exeter, UK, A. K. Srivastava, CSIR-Advanced Materials and Processes Research Institute, Bhopal, India, S. K. R. S. Sankaranarayanan, Center for Nanoscale Materials, Argonne National Laboratory, Argonne, IL, USA, and Department of Mechanical and Industrial Engineering, University of Illinois, Chicago, IL, USA, A. C. Ferrari, Cambridge Graphene Centre, University of Cambridge, Cambridge, UK, and C. S. Bhatia, Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore.

Abstract: “Hard disk drives (HDDs) are used as secondary storage in digital electronic devices owing to low cost and large data storage capacity. Due to the exponentially increasing amount of data, there is a need to increase areal storage densities beyond ~1 Tb/in². This requires the thickness of carbon overcoats (COCs) to be <2 nm. However, friction, wear, corrosion, and thermal stability are critical concerns below 2nm, limiting current technology, and restricting COC integration with heat assisted magnetic recording technology (HAMR). Here we show that graphene-based overcoats can overcome all these limitations, and achieve two-fold reduction in friction and provide better corrosion and wear resistance than state-of-the-art COCs, while withstanding HAMR conditions. Thus, we expect that graphene overcoats may enable the development of 4–10 Tb/in² areal density HDDs when employing suitable recording technologies, such as HAMR and HAMR+bit patterned media.“