Questions tagged [nanoscience]

The study of the performance of ultra-small structures, materials, and devices, usu. usually 0.1 to 100 nm; also, the study of manipulating materials on an atomic or molecular scale. Nanoscience is sometimes used interchangably with Nanotechnology, which is the manipulation of matter on an atomic and molecular scale.

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Would a wireless (stringless) Yo-yo be possible? [closed]

I have this interesting idea for a toy (not a real one, it's for a story). It's a stringless yo-yo that uses electromagnetism to mimic a regular yo-yo. The user wears a ring on their middle finger ...
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Local field enhancement and conservation of energy

When studying Localized Surface Plasmon Resonance (L-SPR) one analyzes the interaction of plane waves with spherical nanoparticles and gets the result that the field $\vec{E}_{in}$ induced inside the ...
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Can second harmonic generation be stronger than fundamental frequency interaction in metals/dielectric nanoparticles?

Quick question regarding non-linear optics: A nanoparticle, either dielectric or metallic present second harmonic generation. The dielectric, following the simplest modelization as: $$E(2\omega)\...
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Carbon nanotube hydrophobicity

Xinyou Ma, Chenghan Li, Alex B. F. Martinson and Gregory A. Voth, Water Assisted Proton Transport in Confined Nanochannels states that carbon nanotube is hydrophobic. That means, as I understand it, ...
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How to calculate the energy required for imaging?

Suppose you would like to investigate atomic core structures with atomic separation $x$Å. How do you calculate the energy required for imaging? Say for an X-ray? Edit: Is it simply a matter of using ...
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Can nanotechnology build a virus? [closed]

I heard that nanotechnology can arrange atoms the way one wishes. The atomic force microscope can control the arrangement. As the composition of the viruses is known, can by nanoprinting a virus be ...
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Can sound be used to identify a molecule?

A few notes to this: Can a molecule have a particular "response" to sound? I understand that soundwaves arise from the synchronisation of millions of particles but assuming such a fine ...
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What are the steps that give rise to this following resistance equation for a diffusive transport of electrons?

$ R = R_b (1 + \frac{\lambda}{L})$ Source - page 6 of this book: https://nanohub.org/courses/FON1/01a/asset/15698
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Why is the Fermi wavelength in a semiconductor larger than in a metal?

I am a high school student, trying to better understand quantum point contacts. Would appreciate a simple explanation if possible. Source: https://arxiv.org/abs/cond-mat/0512609 Since the conductance ...
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Are quantum dot’s immobile?

In a recently closed question regarding the cooling of quantum dots through lasers has one of the commentators state that this is in fact impossible as QD’s are immobile: Can quantum dots temperature ...
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What is wrong in this example with Heisenberg principle?

On Heisenberg principle Suppose an electron is beamed in a nanotube with (width $\Delta x$) on which has been applied a negative voltage so the walls are repealing the electron and it can not approach ...
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Can electromagnetic standing waves be used to move particulates?

As detailed in this paper: https://www.researchgate.net/publication/3941396_Ultrasonic_separation_of_suspended_particles The researchers use the formation of acoustic standing waves to deposit ...
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Dimensionality of bands in bulk materials: modeling interband transitions in Gold with 1D band structure

I'm currently dealing with interband transitions in metal nanoparticles. Geometry-wise they are considered to be a 3D material. Now I've found this paper, where they describe interband transitions in ...
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What dimensions would a quantum confinement system have to be for its electromagnetic emission spectrum to be in the radio section?

Just as specific dimensional restrictions on systems that have quantum confinement like quantum dots lead to the tenability of the emission spectrum of such a system, I was wondering how this idea ...
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Would a macroscopic sphere with the thicknesss of a few atoms behave as an artificial atom?

As quantum dots are composed of closely packed atoms, where their electronic levels are bound and in a confined system, would a similar system, with the same thickness as a quantum dot but much larger ...
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Practical to measure topography of a large area (mm-scale) with scanning probe microscopy (SPM)?

I'm currently very new to nanotechnology. I do understand that it is possible to achieve an excellent topography image of a sample by SPM. However, is it possible to do SPM over a large area (for ...
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Silicon Nano materials

Bulk Si has indirect bandgap structure. But when we make Si into nano particles it behaves like a direct bandgap. Why?
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One Dimensional Heterostructures

Van Der Walls Heterostructures stack different single layer materials together. However, just as a layer of various graphene sheets form graphite with weak bonding in between making the layers easily ...
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Variables in Photoionization and Work Function of metals

Do metals engaged in coordination bond have the same work function and/or photoionization of the pure metal? The outer electron shell still remains the same. If photoionization were to happen, what ...
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Low cost Ultra High Vaccum Chamber and Atomic Force Microscope

Is it possible to build low cost Ultra High Vacuum Chambers and Atomic Force Microscopes? I found a publication about a low cost AFM and I also found instructions for a Ultra High Vacuum chamber. ...
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How do I determine which surface energy of a crystal silicon planes is the lowest? [closed]

If a thin 8” Diameter Single Crystal Silicon (001) substrate is accidentally dropped onto a concrete floor, it will break apart into pieces. By considering only the surface energies of (001), (110) ...
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Could a nanoscopic grain of tungsten moving at ludicrous speed make a sonic boom?

Writing a scifi story about a civilization with mature nanotechnology. Grain of tungsten is a proxy for a nanite. If such a tiny thing as a nanogram of tungsten somehow got accelerated to some truly ...
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How to ease/reduce surface roughness caused by ion sputtering?

I want to investigate the electron emission of samples under electron bombardment. Experts will know that surface condition plays a huge role in the emission rate and some other properties (e.g. max ...
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What causes materials like Vantablack to have their high optical absorption properties?

As per the title of this post. From reading, I understand that blackbody radiation is a factor I should consider here, with light being absorbed and converted to heat etc. However, what I want to ...
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Metasurface holography as a principle behind volumetric displays?

Disclaimer: By no means am I a physicist of any kind so complete inability to grasp complex physical concepts without spending ridiculously unreasonable amounts of time on corresponding research is a ...
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How is ECR (Electron Counting Rule) done in a structure?

I've been told how to apply the ECR to GaAs{001}(2×4) in my lectures but it makes no sense to me and I don't seem to be able to find any other sources that explain this. (This is a further question on ...
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Can we connect several Nano Spacecraft moving at 20% speed of light? [closed]

Nano spacecrafts are one gram silicon chips that will be accelerated to 20% of the speed of light to reach Alpha Centauri in 20 years. I wonder could we connect several spacecraft after they were ...
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Which is the correct GaAs{001}(2×4) structure?

When trying to understand the GaAs 2x4 surface reconstruction, I came across the following statement: "Because the periodicity of the surface has doubled (compared to the bulk periodicity) in the ...
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Does the Thomas-Fermi screening length formula only apply to metals?

Does the Thomas-Fermi screening length formula only apply to metals? In my notes, the Thomas-Fermi screening length is: $\lambda_{TF}^2 = \left(\frac{\pi}{6}\right)^{1/3} \frac{\epsilon(0) a_0}{4n^{1/...
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What is the meaning of "screening-out a perturbation" in a nanosurfaces context?

When reading my lecturer's notes on the Thomas-Fermi screening length, I am told that: "The Thomas-Fermi screening length $\lambda_{TF}$ is a rough guide to how rapidly an electron gas can screen ...
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What is the physical limit to how small semiconductors can get?

Wikipedia shows this history of the progressive miniaturisation of semiconductors: ...
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What is the electron effective mass value for a $\rm InSb$ lattice?

I'm trying to calculate the Thomas-Fermi screening length of the III-V semiconductor $\rm InSb$ with doping level $n = 5 \times 10^{18} \text{cm}^{-3}$ ($5 \times 10^{24} \text{m}^{-3} $ in SI units) ...
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Fermi surface of a spherical nanoparticle

Assume to have a spherical nanoparticle of a metal whose Fermi surface in the crystal is a sphere (I think those are the metals having very symmetric crystals). Would then the Fermi surface be ...
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How to minimize beam walk off during quarter wave plate roration

I am currently building a laser scanning microscope setup. I need to focus the laser on my sample and also place a quarter-wave plate right before the sample so I can control the polarization of the ...
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2 votes
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Is it possible to transfer light between two elements at a distance closer than the wavelength of the light?

Let's say we have a nanoscale laser or led(5nm width/length/height) emitting photons(red, 650nm wavelength) in a direction parallel to its plane, then at 20nm distance in the direction of the emission ...
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Understanding conductivity at nanoscale and validity of Ohm's law

Nanoparticles such as gold and silver are becoming more and more used to print circuit or enhance electrical properties of another material. But I have not been able to find sources that clarify how ...
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DLVO for complex solutions

I am working with a complex solution of 2 proteins and salt. I have been trying to use DLVO (Derjaguin, Landau, Vervey, and Overbeek) theory to get an approximation of the Van Der Waals attractive ...
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Any open-source to animate 2D materials in 3D. (e.g. van der Waals heterostructures, 2D crystal layers etc.)

I want to model different 2D nano-structures, layered materials in 3D (animated version). Is there any open source where I can build these structures?
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What are the properties of the Rice University self-assembling wires?

I've recently watched a video from Rice university, (https://www.youtube.com/watch?v=w1d0Lg6wuvc&t=3s) where they used an electric field to remotely stimulate CNTs to form a wire. This wire was ...
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How to read some certain band diagrams?

I have some problems on understanding some semiconductors band diagram. For instance, I understand quite well something like this: I understand it because it is quite simple: there are the energy ...
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Applications of nanomechanics

What are applications of nanomechanics beyond its use in atomic force microscopy? The question is specifically about the existing applications rather than the potential/future ones (which are quite a ...
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Plausibility of detecting viruses using optical spectra [closed]

Ok, this is a huge long shot, and I also apologise if this is a poor question (I'm a newbie here...). This doesn't seem to me a strictly perfect fit for Chemistry.SE, Biology.SE, or Photography.SE ...
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Is "quaternary" adjective redundant while speaking of InGaAsP?

I'm reading an article. One sentence looks as following: The 500 nm thick waveguide layer consists of an InGaAsP quaternary layer But since InGaAsP is quaternary compound, why do they write ...
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How can a picture of a virus be taken when they are not even 300 nm (wavelength of blue light) long?

We cannot take photos of protons because they are not at least the size of the wavelength that registers into visible light. I see photos of Coronavirus in the news everywhere where there is a clear ...
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What is the difference between non-local optical response and local optical response?

Does anyone knows what is the difference between non-local optical response and local optical response in metal-dielectric-metal?
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What does the density of states of a bulk material, 2DEG, quantum wire and quantum dot tell me?

This is a rather long winded questions so I hope that I can get my questions across as coherent as possible. Background: I am a third Semester Nanoscience student and I am taking my first QM course ...
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Atomic Layer Deposition [closed]

What is "conformality" in atomic layer deposition? As in 1. "recombination of radicals on the sidewalks limits the conformality in high aspect ratio structures" Or in 2. "Key advantage of ALD is ...
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synthesis of free standing silicene

Unlike graphene which can be isolated from graphite via exfoliation, the same thing can't be done with silicene. Most of the papers I see usually involve synthesis of silicene on a metal substrate ...
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How does adding high energy density metallic nanoparticles increases the burning rate during a combustion process?

I have been reading about combustion and oxidation, and I have found out that by adding metallic nanoparticles (e.g aluminium nanoparticles) the burning rate of the propellant increases while the ...
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Difference between electrical conductivity and optical conductivity

Is there any difference between electrical conductivity and optical conductivity? How to explain it physically and is there any method available to connect them mathematically? If I calculate carrier ...
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