Evidence of Critical Tunnelling Width in Ensuring Spin Polarized Asymmetric Negative Differential Resistance Feature in Two‐Dimensional g‐C4N3‐graphene‐g‐C4N3. Issue 27 (14th July 2021)

• Record Type: Journal Article
• Authors: Bhowmick, Rinki; Chattopadhyaya, Mausumi; Sen, Sabyasachi
• Is Part Of: ChemistrySelect. Volume 6:Issue 27(2021)
• Page Start: 6916
• Page End: 6924
• Publication Date: 2021-07-14
• Subjects: Graphene sheet -- tunnel barrier -- spintronics -- spin filter -- negative differential resistance; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.202101583
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: We report herein existence of a critical tunnelling width beyond which graphitic tunnelling nanostructures exhibit asymmetric spin polarized negative differential resistance feature. Our theoretical foray quite clearly establishes that even with a simple two‐dimensional tunnelling nanostructure created by an assembly of ferromagnetic graphitic carbon nitride (g‐C4N3) electrodes separated by insulating graphene sheet of variable lengths, there exists a critical tunnelling width at which the system switches from symmetric to asymmetric negative differential resistance feature. Presence of robust spin filer efficiency (100 %) over a wide range of bias variation (−1.0 to +1.0 V) added with negative differential resistance action makes the device with shorter tunnelling width of 22.36 Å and 31. 96 Å potentially useful as multifunctional spintronic device. However, at the critical tunnelling width of 36.69 Å and beyond the forward bias negative differential resistance features completely switches off and same is observed only in reverse bias. This switching action certainly opens up the prospect of logic gates operation in quantum circuits. Results obtained has been explained through transmission spectra, transmission pathways and molecular projected self‐consistent Hamiltonian states analysis. Emergence of asymmetric I−V curve beyond critical tunnelling width has been explained by examining differences in spin injection coefficients. Abstract : Negative differential resistance (NDR) efficiency (ln scale) variation against tunneling width and switching off asymmetric spin polarized NDR action at forward bias voltage at and above the tunneling width of 36.69 Å featured from a two‐dimensional system sandwiching graphene in between two ferromagnetic graphitic carbon nitride (g‐C4 N3 ) electrodes. Switching action of the proposed material essentially opens its potential usage in the design of logic gates in quantum circuits.