New Delhi: Data encryption and protection are crucial in today's communication systems. The challenge is only going to be compounded with the advancement of Internet of Things (IoT) and Artificial Intelligence (AI) technologies, which either produce large volumes of data continuously or depend on the data for their efficient functionality.

Thus, it has become imperative to develop newer mechanisms that can facilitate the exchange of classified information in a secure way.

Researchers at IIT Delhi have demonstrated one such technique on a commercially available polymeric material called 'Cyclic Transparent Optical Polymer (CYTOP),' which may open new ways of developing advanced electronic devices for inherent data storage and encryption.

The proposed technique is versatile and can be used on various materials, opening up scopes in a wide range of applications, including renewable energy generation from rainwater, chemical sensing for water quality monitoring, etc.

A study titled “Determination of surface charge density and charge mapping of CYTOP thin film in air using Electrostatic Force Microscopy," carried out by research scholar Shalini Singh from the School of Interdisciplinary Research (SIRe) under the guidance of Prof. Dhiman Mallick from the Department of Electrical Engineering and Prof. Ankur Goswami from the Department of Materials Science and Engineering at IIT Delhi and in collaboration with Prof. Stefan A. L. Weber from Max Plank Institute of Polymer Research and University of Stuttgart, Germany, was recently published in ACS Langmuir (Vol 40, 2024,16330-16337: Link: https://doi.org/10.1021/acs.langmuir.4c01504).

The study revealed that CYTOP can hold the inserted charges for a long duration, which is not generally possible with other materials. This property of CYTOP can be utilized to write the information at nanoscale in the form of charges, which can further be read by Electrostatic Force Microscopy (EFM) only.

“The present investigation would allow us to write anything on an electret substrate (material that can store charge indefinitely) by using a suitable charge injection mechanism and can only be retrieved under a specialized instrument using a particular protocol. The written string would not be visible even in optical or electron microscope. The longevity of the written charge is dependent on the quality of the electret we are using. CYTOP has shown significant promises in that front, which can retain charges for more than 100 years.” said Prof. Dhiman Mallick, Department of Electrical Engineering, IIT Delhi.

"In the current study, the Atomic Force Microscope's EFM mode was used to write and read the charges by microcantilever probe on CYTOP. Although this is a very initial step of charge writing capability at nanoscale on an electret but can be extended to the macroscale using motorized stage and probe, like lithographic patterning, which could be end-to-end encrypted,” said Prof. Ankur Goswami, Department of Materials Science and Engineering, IIT Delhi.

Research Scholar Shalini Singh added, “This study may give a direction towards the application for ultra-high sensitive sensors and data storage for the memory devices.”

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