Roger K. Lake

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Graphene exhibits extraordinary electrical properties and is therefore often envisioned to be the candidate material for post-silicon era as Silicon technology approaches fundamental scaling limits. Various Graphene based electronic devices and interconnects have been proposed in the past. In this paper, we explore the possibility of a hybrid fabric between(More)
Simulation of trap-assisted tunneling effect on characteristics of gallium nitride diodes Tuning of terahertz intrinsic oscillations in asymmetric triple-barrier resonant tunneling diodes Repeatable low-temperature negative-differential resistance from Al0.18Ga0.82N/GaN resonant tunneling diodes grown by molecular-beam epitaxy on free-standing GaN(More)
Graphene is an emerging nano-material that has garnered immense research interest due to its exotic electrical properties. It is believed to be a potential candidate for post-Si nanoelectronics due to high carrier mobility and extreme scalability. Recently, a new graphene nanoribbon crossbar (xGNR) device was proposed which exhibits negative differential(More)
We report on an eKcient numerical technique for directly locating transmission resonances and zeros in semiconductor heterostructures using tight-binding multiband models. The quantum transmitting boundary method is employed to generate the inverse of the retarded Green's function G (E) in. the tight-binding representation. The poles of G (E) are located.(More)
A number of the charge-density-wave materials reveal a transition to the macroscopic quantum state around 200 K. We used graphene-like mechanical exfoliation of TiSe 2 crystals to prepare a set of films with different thicknesses. The transition temperature to the charge-density-wave state was determined via modification of Raman spectra of TiSe 2 films. It(More)
Patterning of biomolecules on graphene layers could provide new avenues to modulate their electrical properties for novel electronic devices. Single-stranded deoxyribonucleic acids (ssDNAs) are found to act as negative-potential gating agents that increase the hole density in single-layer graphene. Current-voltage measurements of the hybrid ssDNA/graphene(More)
We report a robust method for engineering the optoelectronic properties of many-layer MoS2 using low-energy oxygen plasma treatment. Gas phase treatment of MoS2 with oxygen radicals generated in an upstream N2 -O2 plasma is shown to enhance the photoluminescence (PL) of many-layer, mechanically exfoliated MoS2 flakes by up to 20 times, without reducing the(More)
Graphene is an emerging nanomaterial believed to be a potential candidate for post-Si nanoelectronics due to its exotic properties. Recently, a new <i>graphene nanoribbon crossbar</i> (xGNR) device was proposed which exhibits <i>negative differential resistance</i> (NDR). In this article, a multistate memory design is presented that can store multiple bits(More)
Graphene revealed a number of unique properties beneficial for electronics. However, graphene does not have an energy band-gap, which presents a serious hurdle for its applications in digital logic gates. The efforts to induce a band-gap in graphene via quantum confinement or surface functionalization have not resulted in a breakthrough. Here we show that(More)
We report circularly polarized photolumines-cence spectra taken from few layer MoS 2 after treatment with a remotely generated oxygen plasma. Here, the oxygen plasma decouples the individual layers in MoS 2 by perturbing the weak interlayer van der Waals forces without damaging the lattice structure. This decoupling causes a transition from an indirect to a(More)