4 research outputs found
Fermi Level Pinning at Electrical Metal Contacts of Monolayer Molybdenum Dichalcogenides
Electrical
metal contacts to two-dimensional (2D) semiconducting
transition metal dichalcogenides (TMDCs) are found to be the key bottleneck
to the realization of high device performance due to strong Fermi
level pinning and high contact resistances (<i>R</i><sub>c</sub>). Until now, Fermi level pinning of monolayer TMDCs has been
reported only theoretically, although that of bulk TMDCs has been
reported experimentally. Here, we report the experimental study on
Fermi level pinning of monolayer MoS<sub>2</sub> and MoTe<sub>2</sub> by interpreting the thermionic emission results. We also quantitatively
compared our results with the theoretical simulation results of the
monolayer structure as well as the experimental results of the bulk
structure. We measured the pinning factor <i>S</i> to be
0.11 and −0.07 for monolayer MoS<sub>2</sub> and MoTe<sub>2</sub>, respectively, suggesting a much stronger Fermi level pinning effect,
a Schottky barrier height (SBH) lower than that by theoretical prediction,
and interestingly similar pinning energy levels between monolayer
and bulk MoS<sub>2</sub>. Our results further imply that metal work
functions have very little influence on contact properties of 2D-material-based
devices. Moreover, we found that <i>R</i><sub>c</sub> is
exponentially proportional to SBH, and these processing parameters
can be controlled sensitively upon chemical doping into the 2D materials.
These findings provide a practical guideline for depinning Fermi level
at the 2D interfaces so that polarity control of TMDC-based semiconductors
can be achieved efficiently
Modulation of Quantum Tunneling <i>via</i> a Vertical Two-Dimensional Black Phosphorus and Molybdenum Disulfide p–n Junction
Diverse diode characteristics
were observed in two-dimensional
(2D) black phosphorus (BP) and molybdenum disulfide (MoS<sub>2</sub>) heterojunctions. The characteristics of a backward rectifying diode,
a Zener diode, and a forward rectifying diode were obtained from the
heterojunction through thickness modulation of the BP flake or back
gate modulation. Moreover, a tunnel diode with a precursor to negative
differential resistance can be realized by applying dual gating with
a solid polymer electrolyte layer as a top gate dielectric material.
Interestingly, a steep subthreshold swing of 55 mV/dec was achieved
in a top-gated 2D BP–MoS<sub>2</sub> junction. Our simple device
architecture and chemical doping-free processing guaranteed the device
quality. This work helps us understand the fundamentals of tunneling
in 2D semiconductor heterostructures and shows great potential in
future applications in integrated low-power circuits
Il futuro del personalismo fra etica e politica
Il personalismo rappresenta nella storia del pensiero politico una posizione che intende superare sia l'individualismo sia il collettivismo. Caratteristica fondamentale delle diverse concezioni del personalismo è la sua disposizione a difendere la sfera dell'uomo dalle invadenze di poteri assoluti e dispotici, che nel mondo contemporaneo assumono il volto del totalitarismo .Con la fine delle ideologie e la caduta delle utopie, il personalismo ha anche la funzione di criticare la tendenza delle società liberaldemocratiche e consumiste verso nuove forme di anomie e di controllo sociale della persona con la potenza dei nuovi media.Personality represents in the history of political thought a position that goes beyond both individualism and collectivism. The fundamental feature of the different conceptions of personalism is its disposition to defend the sphere of man from the invasions of absolute and despotic powers that in the contemporary world assume the face of totalitarianism. With the end of ideologies and the fall of utopias, personalism has It is also the function of criticizing the tendency of liberaldemocratic and consumer societies towards new forms of anomie and social control of the person with the power of the new media
Targeted Intraceptor Nanoparticle Therapy Reduces Angiogenesis and Fibrosis in Primate and Murine Macular Degeneration
Monthly intraocular injections are widely used to deliver protein-based drugs that cannot cross the blood-retina barrier for the treatment of leading blinding diseases such as age-related macular degeneration (AMD). This invasive treatment carries significant risks, including bleeding, pain, infection, and retinal detachment. Further, current therapies are associated with a rate of retinal fibrosis and geographic atrophy significantly higher than that which occurs in the described natural history of AMD. A novel therapeutic strategy which improves outcomes in a less invasive manner, reduces risk, and provides long-term inhibition of angiogenesis and fibrosis is a felt medical need. Here we show that a single intravenous injection of targeted, biodegradable nanoparticles delivering a recombinant <i>Flt23k</i> intraceptor plasmid homes to neovascular lesions in the retina and regresses CNV in primate and murine AMD models. Moreover, this treatment suppressed subretinal fibrosis, which is currently not addressed by clinical therapies. Murine vision, as tested by OptoMotry, significantly improved with nearly 40% restoration of visual loss induced by CNV. We found no evidence of ocular or systemic toxicity from nanoparticle treatment. These findings offer a nanoparticle-based platform for targeted, vitreous-sparing, extended-release, nonviral gene therapy