Effects of uniaxial strain on the performance of armchair graphene nanoribbon resonant tunneling diode

Abstract

Electronic performance of armchair graphene nanoribbon (AGNR) resonant tunneling diodes (RTDs) is influenced by strain effects, when they are mounted on the stretchable substrates or mechanically deformed due to real working conditions. Therefore, it is important to investigate how uniaxial strain can impact the performance of AGNR RTDs. In this paper, two platforms of AGNR RTD namely width-modified AGNR RTD and field-modified AGNR RTD are introduced and they are under both compressive and tensile uniaxial strain. It is found that the characteristics of AGNR RTD change considerably under either compressive or tensile strain. In particular, peak to valley ratio (PVR) can be totally deteriorated upon strong enough whole-body strain. However, local strain in the channel and barrier regions, in contrast to whole-body strain, can even improve the efficiency of AGNR RTD devices. Furthermore, the behavior of strained AGNR RTD is investigated while the width of device is modified. Numerical tight binding coupled with non-equilibrium Green's function is derived for this study to calculate corresponding Hamiltonian matrices and transport properties.

Performance enhancement of armchair graphene nanoribbon resonant tunneling diode using V-shaped potential well

“…For example, the undoped GNR RTD exhibits high PVR ( 10 4 ) by just introducing quantum dots into the nanoribbon [47]. Pristine AGNR based RTD also shows improved performance through local strain in the channel and barrier regions [27]. AGNR based field effect transistors embedded with nanopores exhibits improved I p and PVR with lower well width and drain voltage respectively [48].…”

“…Here, the current flow does not suffer from low carrier mobility and charge storage effects, thereby giving rise to extremely fast operating devices with abrupt turn-on and turn-off facilities. Recently, the study of NDR in graphene has drawn potential research interest due to the feasibility of making a quantum well (QW) structure out of a single graphene sheet through structural modifications [26][27][28][29]. Double barrier quantum well (DBQW) structures have been realized by adjusting the width of armchair graphene nanoribbon (AGNR) to obtain NDR.…”

Antidote-induced armchair graphene nanoribbon based resonant tunneling diodes

“…For an applied voltage, the quasi-quantized states shift to lower energy and, when the Fermi level of the source becomes aligned with the quasi-quantized states, the maximum current, I peak , occurs. In the high bias, when the quantized level goes below the Fermi [46] Graphene/h-BN heterostructure 3.9 Zoghi and Goharrizi [20] Strain-induced (ε = 5%) 5.63 Zoghi and Kabir [47] Width-modified 15-AGNR RTD (0% strain) 3.49 Field-modified 15-AGNR RTD (0% strain) 17.83 Goharrizi et al [48] Antidote 3.31 Doping 1.09 Antidote/doping 9.46 energy, the current starts decreasing and it contributes to the valley current (I valley ).…”

Strain Engineering of Graphene Nanoribbon Transistors Made Using Analytical Quasi-Ballistic Transport Model

“…Moreover, the application of uniaxial strain has been proposed in order to achieve negative differential resistance (NDR) in graphene tunnel FETs [22] as well as in AGNR-based devices [23]. It has also been shown that the characteristics of AGNR resonant tunneling diodes are significantly influenced by uniaxial strain [24,25].…”