Enhanced Optoelectronic Properties of Bilayer Graphene/HgCdTe-Based Single- and Dual-Junction Photodetectors in Long Infrared Regime

Enhanced Photoelectric Properties of Multilayer Graphene Mg2Si/Si Heterojunction Photodetector

“…The band shift reduces the MLG bandgap to 0.14 eV. This observation is consistent with the conclusion made in [18] that the energy level of Graphene shifts close to the valence band. The peak barrier is observed at the conduction band of the Mg2Si/Si heterojunction interface.…”

“…As shown in the energy band diagram (Figure 2), by adding one or more layers of Graphene, a potential well is formed at the Graphene/Mg2Si interface. The p-type doping in the Graphene layers also causes a shift in the energy level of Graphene towards the valence band direction, hence increasing the barrier height [18]. Without light, the transport of carriers became difficult hence the dark current is decreased.…”

“…This further excites another valence band electron to the conduction band. Therefore, in Graphene, corresponding to an incident photon, the impact ionization phenomenon results in generating multiple hot carriers [18]. For the incident light with the wavelength between 400 nm to 600 nm, the EQE of the Mg2Si/Si heterojunction PD is larger than that of the MLG/Mg2Si/Si heterojunction PD.…”

“…Dark current density can be reduced by chemically doped bandgap engineering, or by using two or more Graphene layers [16,17]. In addition, it has been shown that by p-type doping in the Graphene layers the Fermi level of Graphene can be moved near the valence band [18] thus the barrier height is increased. This produces a wide range of effects on the depletion region and the high built-in electric field at the interface.…”

Multifrequency Data Parallel Spin Wave Logic Gates

“…However, when entering into the deca-nanometer regime CMOS downscaling becomes more difficult due to: (i) leakage wall 4,5 , (ii) reliability wall 6 , and (iii) cost wall 4,6 , which suggests the near end of Moore's law. As a result, different technologies, e.g., graphene [7][8][9][10][11] , memristor [12][13][14][15][16] , spintronics [17][18][19][20][21] have been explored in an attempt to meet the exponentially increasing computing market demands 22 .…”