Highly Efficient and Tunable Filtering of Electrons' Spin by Supramolecular Chirality of Nanofiber-Based Materials.

Chidambar Kulkarni,Mathijs F J Mabesoone,Ron Naaman,E W Meijer,Francesco Tassinari,Gal Grinbom,Tapan Kumar Das,Amit Kumar Mondal

doi:10.1002/adma.201904965

Abstract

Organic semiconductors and organic-inorganic hybrids are promising materials for spintronic-based memory devices. Recently, an alternative route to organic spintronic based on chiral-induced spin selectivity (CISS) is suggested. In the CISS effect, the chirality of the molecular system itself acts as a spin filter, thus avoiding the use of magnets for spin injection. Here, spin filtering in excess of 85% in helical π-conjugated materials based on supramolecular nanofibers at room temperature is reported. The high spin-filtering efficiency can even be observed in nanofibers assembled from mixtures of chiral and achiral molecules through chiral amplification effect. Furthermore and most excitingly, it is shown that both "up" and "down" orientations of filtered spins can be obtained in a single enantiopure system via the temperature-dependent helicity (P and M) inversion of supramolecular nanofibers. The findings showcase that materials based on helical noncovalently assembled systems are modular platforms with an emerging structure-property relationship for spintronic applications.

Highlights

In organic magnetoresistance devices, the spins are injected from ferfor spintronic-based memory devices
Spin filtering in excess of 85% in helical π-conjugated materials based on supramolecular nanofibers romagnetic electrodes and the current is affected by the external magnetic field.[7]
The findings showcase that materials toward organic spintronics, which is based on the chiral-induced spin selectivity (CISS) effect was suggested.[8,9]

Summary

Introduction

In organic magnetoresistance devices, the spins are injected from ferfor spintronic-based memory devices. We present results showing unparalleled spin selection, using π-conjugated molecular materials based on coronene bisimide and tetra-amidated porphyrin cores appended with either chiral or achiral alkoxyphenyl groups (Figure 1a).

Objectives

Results

Conclusion