3,446 research outputs found
Transmission of doughnut light through a bull's eye structure
We experimentally investigate the extraordinary optical transmission of
doughnut light through a bull's eye structure. Since the intensity is vanished
in the center of the beam, almost all the energy reaches the circular
corrugations (not on the hole), excite surface plasmons which propagate through
the hole and reradiate photons. The transmitted energy is about 57 times of the
input energy on the hole area. It is also interesting that the transmitted
light has a similar spatial shape with the input light although the diameter of
the hole is much smaller than the wavelength of light.Comment: 3 pages,4 figure
Effect of gate voltage on spin transport along -helical protein
Recently, the chiral-induced spin selectivity in molecular systems has
attracted extensive interest among the scientific communities. Here, we
investigate the effect of the gate voltage on spin-selective electron transport
through the -helical peptide/protein molecule contacted by two
nonmagnetic electrodes. Based on an effective model Hamiltonian and the
Landauer-B\"uttiker formula, we calculate the conductance and the spin
polarization under an external electric field which is perpendicular to the
helix axis of the -helical peptide/protein molecule. Our results
indicate that both the magnitude and the direction of the gate field have a
significant effect on the conductance and the spin polarization. The spin
filtration efficiency can be improved by properly tuning the gate voltage,
especially in the case of strong dephasing regime. And the spin polarization
increases monotonically with the molecular length without the gate voltage,
which is consistent with the recent experiment, and presents oscillating
behavior in the presence of the gate voltage. In addition, the spin selectivity
is robust against the dephasing, the on-site energy disorder, and the space
angle disorder under the gate voltage. Our results could motivate further
experimental and theoretical works on the chiral-based spin selectivity in
molecular systems.Comment: 8 pages, 7 figure
Chatbots in Drug Discovery: A Case Study on Anti-Cocaine Addiction Drug Development with ChatGPT
The birth of ChatGPT, a cutting-edge language model chatbot developed by
OpenAI, ushered in a new era in AI, and this paper vividly showcases its
innovative application within the field of drug discovery. Focused specifically
on developing anti-cocaine addiction drugs, the study employs GPT-4 as a
virtual guide, offering strategic and methodological insights to researchers
working on generative models for drug candidates. The primary objective is to
generate optimal drug-like molecules with desired properties. By leveraging the
capabilities of ChatGPT, the study introduces a novel approach to the drug
discovery process. This symbiotic partnership between AI and researchers
transforms how drug development is approached. Chatbots become facilitators,
steering researchers towards innovative methodologies and productive paths for
creating effective drug candidates. This research sheds light on the
collaborative synergy between human expertise and AI assistance, wherein
ChatGPT's cognitive abilities enhance the design and development of potential
pharmaceutical solutions. This paper not only explores the integration of
advanced AI in drug discovery but also reimagines the landscape by advocating
for AI-powered chatbots as trailblazers in revolutionizing therapeutic
innovation
Enhancing the machine vision performance with multi-spectral light sources
This study mainly focuses on the performance of different multi-spectral
light sources on different object colors in machine vision and tries to enhance
machine vision with multi-spectral light sources. Using different color pencils
as samples, by recognizing the collected images with two classical neural
networks, AlexNet and VGG19, the performance was investigated under 35
different multi-spectral light sources. The results show that for both models
there are always some non-pure white light sources, whose accuracy is better
than pure white light, which suggests the potential of multi-spectral light
sources to further enhance the effectiveness of machine vision. The comparison
of both models is also performed, and surprised to find that the overall
performance of VGG19 is lower than that of AlexNet, which shows that the
importance of the choice of multi-spectral light sources and models.Comment: 12 pages, 7 figure
Coupling of light from an optical fiber taper into silver nanowires
We report the coupling of photons from an optical fiber taper to surface
plasmon modes of silver nanowires. The launch of propagating plasmons can be
realized not only at ends of the nanowires, but also at the midsection. The
degree of the coupling can be controlled by adjusting the light polarization.
In addition, we present the coupling of light into multiple nanowires from a
single optical fiber taper simultaneously. Our demonstration offers a novel
method for optimizing plasmon coupling into nanoscale metallic waveguides and
promotes the realization of highly integrated plasmonic devices.Comment: 5 pages, 4 figure
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