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arXiv · 2102.01596

Role of Defect Induced Interfacial States in Molecular Sensing: Ultrahigh- Sensitive Region for Molecular Interaction

Rahul Tripathi·Pritam Bhattacharyya·Alok Shukla·Abha Misra
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Abstract

The defect induced interfacial states are created in an atomically thin two-dimensional molybdenum disulfide channel by underlying a narrow pattern of a graphene layer in a field effect transistor. Nondestructive method for the generation of charge-state allowed a highly sensitive molecular interaction with the sensitivity of nearly three-order of magnitude at room temperature. The presence of interfacial states in the channel lead to a conductance fluctuation and its magnitude is modulated using the nitrogen dioxide gas molecules in the subthreshold region. The study provides a systematic approach to establish a correlation between modulated conductance fluctuation and the molecular concentration upto parts-per-billion. First-principles density functional theory further explains the role of unique interfacial configuration on conductance fluctuation. Therefore, our study demonstrates an experimental approach to induce charge-state for the modulation of carrier concentration and exploits the role of defect induced interfacial states in atomically thin interfaces for the molecular interaction.

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Rahul Tripathi, Pritam Bhattacharyya, Alok Shukla, Abha Misra. 2021-02-02. Role of Defect Induced Interfacial States in Molecular Sensing: Ultrahigh- Sensitive Region for Molecular Interaction. https://doi.org/10.1103/physrevapplied.14.054014

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