Full spin polarization and pure spin current produced in the metallic CuC6 photodetector

Abstract

This paper examines the linear and elliptical photogalvanic effects in the armchair and zigzag CuC₆ photodetectors with the CuC₆ monolayer being a planar and metallic two-dimensional material, and investigates the influences of point-defects and its potentials on the applications of optoelectronic and spintronic devices. The results demonstrated that due to the decreasing of symmetry from D_2H to C_2v or C_s for the CuC₆ monolayer because of the introducing of point defects, the armchair and zigzag CuC₆ photodetectors possess robust linear photogalvanic effect, and especially for the Cu-doping-C₁ case there can produce greatly high photocurrents with the largest values as 8 a₀²/photon and 46 a₀²/photon respectively, which are enough to be experimentally detected. Moreover, elliptical photogalvanic effect can further enhance the photocurrents based on the linear photogalvanic effect. More critically, 100 % full spin polarization and pure spin currents coexisted in all conditions, including pristine, vacancy and substitution doping cases, showing two CuC₆ photodetectors are highly superior spin current generating photoelectronic and spintronic devices, exhibiting extremely significant research values. In addition, two CuC₆ photodetectors at different point-defect situations indicate exceptional sensitivity on polarization detection. Therefore, by elucidating the interrelationship between structure symmetry, types of point defect and spin current generation, this paper broadens the scopes on the applications of this metallic CuC₆ monolayer in optoelectronics and spintronics.