2017/09/03 by Partha Goswami, Goswami, Partha
Materials Science · Physics and Astronomy · #2D Materials and Applications #FOS: Physical sciences #Graphene research and applications #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.1709.00667
openalex publication_date 2017/09/03 · openalex created_date 2022/10/03 · openalex updated_date 2026/07/28
The spin and valley polarizations and plasmonics in Van der Waals\nheterostructures of strained graphene monolayer on 2D transition metal\ndichalcogenide (GrTMD) substrate are reported in this communication. The\nsubstrate induced interactions (SII) involve sub-lattice-resolved, and enhanced\nintrinsic spin-orbit couplings, the extrinsic Rashba spin-orbit coupling\n(RSOC), and the orbital gap related to the transfer of the electronic charge\nfrom graphene to the substrate. Furthermore, magnetic impurity atoms are\ndeposited to the graphene surface and the corresponding exchange field is\nincluded in the band dispersion. A Rashba coupling dependent pseudo Zeeman term\narising due to the interplay of SIIs was found to be responsible for the spin\ndegeneracy lifting and the spin polarization. The latter turns out to be\nelectrostatic doping and the exchange field tunable and inversely proportional\nto the square root of the carrier concentration. The strain field, on the other\nhand, brings about the valley polarization. The intra-band plasmon dispersion\nfor the finite doping and the long wavelength limit has also been obtained. The\ndispersion involves the q2/3 behavior and not the well known q1/2 behavior. The\nuniform, uniaxial strain does not bring about any change in this behavior.\nHowever, the plasmon dispersion gets steeper for the wavevector perpendicular\nto the direction of strain and is flattened for wave vectors along the\ndirection of the strain with the term responsible for the flattening\nproportional to the strain field. The stronger confinement capability of GrTMD\nPlasmon compared to that of standalone, doped graphene is an important outcome\nof the present work. One finds that whereas the intra-band absorbance of GrTMD\nis decreasing function of the frequency at a given strain field, it is an\nincreasing function of the strain field at a given frequency.\n