Do you want to publish a course? Click here

Quantum interference effects on the noise power in the CNT/aGNR/CNT junction

101   0   0.0 ( 0 )
 Added by Javad Vahedi
 Publication date 2014
  fields Physics
and research's language is English




Ask ChatGPT about the research

Based on tight-binding model and a generalized Greens function method in Landauer-Buttiker formalism, the effects of quantum interference (QI) on the noise power and Fano factor of an armchair graphene nanoribbon (aGNR) sandwiched between infinite single wall carbon nanotube (SWCNT) as a CNT/aGNR/CNT system are numerically investigated. In this work, changing the aGNR to CNT electrodes contact positions and applying the magnetic field as two sources of QI are considered. We have found different Fano-resonance and anti-resonance peaks on the transmission probability in the presence of QI sources that show profound effects on the current-voltage characteristics and noise power. Our results also show that the shot noise characteristic, either in the Poisson limit ($F=1$) or sub-Poisson limit ($F<1$), and also maximum value of the Fano factor strongly depend on the aGNR to CNT electrodes contact positions and the magnetic field strength. These results can be useful for designing the future nano-electronic devices.



rate research

Read More

Using the tight-binding model and the generalized Greens function formalism, the effect of quantum interference on the electron transport through the benzene molecule in a semiconductor/benzene/semiconductor junction is numerically investigated. We show how the quantum interference sources, different contact positions and local gate, can control the transmission characteristics of the electrode/molecule/electrode junction. We also study the occurrence of anti-resonant states in the transmission probability function using a simple graphical scheme (introduced in Ref.[Phys. Chem. Chem. Phys, 2011, 13, 1431]) for different geometries of the contacts between the benzene molecule and semiconductor(silicon and titanium dioxide) electrodes.
Overdense plasmas have been attained with 2.45 GHz microwave heating in the low-field, low-aspect-ratio CNT stellarator. Densities higher than four times the ordinary (O) mode cutoff density were measured with 8 kW of power injected in the O-mode and, alternatively, with 6.5 kW in the extraordinary (X) mode. The temperature profiles peak at the plasma edge. This was ascribed to collisional damping of the X-mode at the upper hybrid resonant layer. The X-mode reaches that location by tunneling, mode-
Over-screened Kondo effect is feasible in carbon nanotube quantum dot junction hosting a spin $tfrac{1}{2}$ atom with single $s$-wave valence electron (e.g Au). The idea is to use the two valleys as two symmetry protected flavor quantum numbers $xi={bf K}, {bf K}$. Perturbative RG analysis exposes the finite weak-coupling two-channel fixed point, where the Kondo temperature is estimated to be around $0.5div5$~K. Remarkably, occurrence of two different scaling regimes implies a non-monotonic dependence of the conductance as function of temperature.
Effects of disorder on the electronic transport properties of graphene are strongly affected by the Dirac nature of the charge carriers in graphene. This is particularly pronounced near the Dirac point, where relativistic charge carriers cannot efficiently screen the impurity potential. We have studied time-dependent conductance fluctuations and magnetoresistance in graphene in the close vicinity of the Dirac point. We show that the fluctuations are due to the quantum interference effects due to scattering on impurities, and find an unusually large reduction of the relative noise power in magnetic field, possibly indicating that an additional symmetry plays an important role in this regime.
Ionic Liquids (ILs) are organic molten salts characterized by the total absence of solvent. They show remarkable properties: low vapor pressure, high ionic conductivity, high chemical, thermal and electrochemical stability. These electrolytes meet therefore key criteria for the development of safe energy storage systems. Due to a competition between electrostatic and van der Walls interactions, ILs show an uncommon property for neat bulk liquids: they self-organize in transient nanometric domains. In ILs-based electrochemical devices, this fluctuating nano-segregation acts as energy barriers to the long range diffusional processes and hence to the ionic conductivity. Here, we show how the ionic conductivity of ILs can be increased by more than one order of magnitude by exploiting one dimensional (1D) confinement effects in macroscopically oriented carbon nanotube (CNT) membranes. We identify 1D CNT membranes as promising separators for high instant power batteries.
comments
Fetching comments Fetching comments
Sign in to be able to follow your search criteria
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا