Trapping the carrier in the spin-locked MoS2 atomic valley by absorption of chiral L-cysteine

TL;DR

This study demonstrates how chiral L-cysteine enhances valley contrasting spin-momentum locked states in monolayer MoS2, potentially improving valleytronic devices at ambient conditions.

Contribution

It reveals a novel method of stabilizing valley polarization in MoS2 through chiral molecule adsorption, advancing valleytronics at room temperature.

Findings

Enhanced valley polarization observed with L-cysteine modification.

Chiral L-cysteine stabilizes in-plane magnetic fields, reducing intervalley relaxation.

Potential applications in valley-based LEDs and information encoding.

Abstract

This work, demonstrate enhanced valley contrasting spin-momentum locked chiral states at van der Waal interface of chiral L-cysteine and mono-atomically thin MoS2 placed at Si/SiO2 substrate at ambient condition. Helicity dependent photoluminescence and resonance Raman measurement highlights spin-locked transitions for chiral L-cysteine modified SL MoS2 at ambient condition. Selective adsorption of chiral L-cysteine dimer /cystine on monolayer MoS2, stabilizes the in-plane effective magnetic field due to Si/SiO2 substrate and blocks the intervalley spin relaxation. The observed polarisation efficiency will be useful for improving the functionality of valley-based light emitting diode (LEDs) and encoding information in logical devices.