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Title: Dual function armchair graphene nanoribbon-based spin-photodetector: Optical spin-valve and light helicity detector

Abstract

We show an armchair graphene nanoribbon channel connected between asymmetric ferromagnetic source-drain structure—i.e., p-type Co/Au/graphene source and n-type Co/Cu/graphene drain—can operate as dual function spin-photodetector, under zero external biases at room temperature. It can function as an optical spin-valve with magnetoresistance of greater than 60% and responsivity as high as 25.12 A/mW, when irradiated by an un-polarized light of energy ∼3.03 eV. Under a circularly polarized illumination, this optical spin-valve can also operate as a light helicity detector. The calculated magnetoresistances for right and left circularly polarized lights are both greater than 60%.

Authors:
 [1];  [1];  [2]
  1. Department of Physics, Tarbiat Modares University, P.O. Box 14115-335, Tehran 1411713116 (Iran, Islamic Republic of)
  2. (ADSL), Tarbiat Modares University, P.O. Box 14115-194, Tehran 1411713116 (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
22310891
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; ASYMMETRY; COBALT; COPPER; EV RANGE; GOLD; GRAPHENE; HELICITY; ILLUMINANCE; IRRADIATION; MAGNETORESISTANCE; NANOSTRUCTURES; PHOTODETECTORS; P-TYPE CONDUCTORS; SPIN; TEMPERATURE RANGE 0273-0400 K; VISIBLE RADIATION

Citation Formats

Ostovari, Fatemeh, Moravvej-Farshi, Mohammad Kazem, E-mail: Farshi-k@modares.ac.ir, and Faculty of Electrical and Computer Engineering, Advanced Devices Simulation Lab. Dual function armchair graphene nanoribbon-based spin-photodetector: Optical spin-valve and light helicity detector. United States: N. p., 2014. Web. doi:10.1063/1.4893604.
Ostovari, Fatemeh, Moravvej-Farshi, Mohammad Kazem, E-mail: Farshi-k@modares.ac.ir, & Faculty of Electrical and Computer Engineering, Advanced Devices Simulation Lab. Dual function armchair graphene nanoribbon-based spin-photodetector: Optical spin-valve and light helicity detector. United States. doi:10.1063/1.4893604.
Ostovari, Fatemeh, Moravvej-Farshi, Mohammad Kazem, E-mail: Farshi-k@modares.ac.ir, and Faculty of Electrical and Computer Engineering, Advanced Devices Simulation Lab. Mon . "Dual function armchair graphene nanoribbon-based spin-photodetector: Optical spin-valve and light helicity detector". United States. doi:10.1063/1.4893604.
@article{osti_22310891,
title = {Dual function armchair graphene nanoribbon-based spin-photodetector: Optical spin-valve and light helicity detector},
author = {Ostovari, Fatemeh and Moravvej-Farshi, Mohammad Kazem, E-mail: Farshi-k@modares.ac.ir and Faculty of Electrical and Computer Engineering, Advanced Devices Simulation Lab},
abstractNote = {We show an armchair graphene nanoribbon channel connected between asymmetric ferromagnetic source-drain structure—i.e., p-type Co/Au/graphene source and n-type Co/Cu/graphene drain—can operate as dual function spin-photodetector, under zero external biases at room temperature. It can function as an optical spin-valve with magnetoresistance of greater than 60% and responsivity as high as 25.12 A/mW, when irradiated by an un-polarized light of energy ∼3.03 eV. Under a circularly polarized illumination, this optical spin-valve can also operate as a light helicity detector. The calculated magnetoresistances for right and left circularly polarized lights are both greater than 60%.},
doi = {10.1063/1.4893604},
journal = {Applied Physics Letters},
number = 7,
volume = 105,
place = {United States},
year = {Mon Aug 18 00:00:00 EDT 2014},
month = {Mon Aug 18 00:00:00 EDT 2014}
}
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