Reversible, opto-mechanically induced spin-switching in a nanoribbon-spiropyran hybrid material

Abstract

It has recently been shown that electronic transport in zigzag graphene nanoribbons becomes spin-polarized upon application of an electric field across the nanoribbon width. However, the electric fields required to experimentally induce this magnetic state are typically large and difficult to apply in practice. Here, using both first-principles density functional theory (DFT) and time-dependent DFT, we show that a new spiropyran-based, mechanochromic polymer noncovalently deposited on a nanoribbon can collectively function as a dual opto-mechanical switch for modulating its own spin-polarization. These calculations demonstrate that upon mechanical stress or photoabsorption, the spiropyran chromophore isomerizes from a closed-configuration ground-state to a zwitterionic excited-state, resulting in a large change in dipole moment that alters the electrostatic environment of the nanoribbon. We show that the electronic spin-distribution in the nanoribbon-spiropyran hybrid material can be reversibly modulated via noninvasive optical and mechanical stimuli without the need for large external electric fields. Our results suggest that the reversible spintronic properties inherent to the nanoribbon-spiropyran material allow the possibility of using this hybrid structure as a resettable, molecular-logic quantum sensor where opto-mechanical stimuli are used as inputs and the spin-polarized current induced in the nanoribbon substrate is the measured output.

Effect of graphene oxide on the structural and electrochemical behavior of polypyrrole deposited on cotton fabric

“…Conversely, the non-covalent physisorption inherently driven by favorable molecular self-assembly involves dispersive interactions. This process does not remarkably modify the band structure properties, leaving the exceptional electronic structure of the graphene derivatives [25]. This strategy is predicted to be one of the keys to solve the drawbacks of common doping processes [24,25].…”

“…This process does not remarkably modify the band structure properties, leaving the exceptional electronic structure of the graphene derivatives [25]. This strategy is predicted to be one of the keys to solve the drawbacks of common doping processes [24,25]. To date, much work has been carried out to develop GO-based nanomaterials in order to study their applications in biosensors, electronics and optoelectronics [23,26].…”

“…In other kinds of doping, which is basically the functionalization of graphene by non-covalent bonding, no defects are generated. Nevertheless, functionalization of graphene by covalent bonding possesses similar drawbacks to the common doping technique because defects generation decreases mobility and the on/off ratio in a graphene field-effect transistor [25]. Conversely, the non-covalent physisorption inherently driven by favorable molecular self-assembly involves dispersive interactions.…”

Layer by layer assembled films between hemoglobin and multiwall carbon nanotubes for pH-switchable biosensing

“…The development of the devices was mainly based on their controllable responses to external stimuli [7], such as stress [8], temperature [9], pH value [10], moisture [11], light [12], and ionic strength [13].…”

Enhanced magnetoimpedance effect of carbon fiber/Fe-based alloy coaxial composite by tensile stress

“…Considering their new and/or enhanced functionalities that cannot be achieved by either component alone, the composites hold great promise for a wide variety of applications in optoelectronic materials [4], biomedical field [5] , magnetoelectric coupling [6,7]. As a kind of quasi-one-dimensional material, carbon fiber could be bound, weaved, and stretched.…”