The phonons tag has no wiki summary.
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Ballistic Conduction - Difference between Bosonic and Fermionic Transport
Ballistic Conduction is the phenomenon of an ideal conduction environment for quantum particles - for electrons the Ballistic Conduction is not infinity, but is proportional to the difference between ...
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What is the mathematical justification for the quadratic approximation to the energy of a spring in a one-dimensional lattice?
It follows easily from this draw, the length $l$ of this spring as a function of the vertical distance $x$, as $l(x)=\sqrt{1+x^{2}}$
Now, $l$ can be expressed as a MacLaurin expansion:
$$l(x) = ...
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Reciprocal lattice and phonon
As we obtain a reciprocal lattice for a given crystal we see that discrete values of wavevectors are allowed but a phonon wavevector spectrum is a continuum. Is there a relation between reciprocal ...
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Real World measurements related to phonon dispersion
I hope no one objects to the style of this question. Let me explain my motives in asking the question first.
Condensed matter physics is one of the most beautiful subjects around. But those who are ...
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Where to learn Temperature Dependent Conductivity induced by Electron-Phonon Interaction? [closed]
I want to learn how to calculate the temperature dependent conductivity induced by electron-phonon interaction.
I know in low temperature, the resistance in metal $\rho$ is proportional to $T^5$, $T$ ...
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What is the first paper to report observations of polaritons?
I am seeking references to the first articles regarding the observation of polaritons.
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Phonon-polariton literature resources? [closed]
What is a good resource for studying phonon-polaritons?
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Is it possible to reduce the sound, when two metal objects collide (perhaps with some coating) without reducing the rigidity of the surface?
I have a system, where there are ball bearings on the pistons that clamp the metal plate with special dents for ball bearings. The system should be precise, because it is used for microscopy. It also ...
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Lagrangian of 2D square lattice of point masses connected by springs
Zee's QFT book mentions the Lagrangian of a square 2D horizontal lattice of point masses, connected by springs, and considering only vertical displacements $q_{i}$, as
$ L = \frac{1}{2} ...
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Why do phonons cause excellent heat conduction in diamonds?
Phonons are the quantum of lattice vibrations in crystals and are not to be confused with photons, the gauge bosons of the electromagnetic force. Apparently, they contribute to heat conduction, but I ...
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4answers
363 views
Do we say that phonon has effective mass through its dispersion relation?
The effective mass is proportional to the second derivative of the dispersion relation d2k/dE2.
Do we say that phonon have effective mass through it ? Spin wave have.
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Are there devices which convert thermal energy to electric energy?
Converting optical energy to electric energy is a huge business based on the photovoltaic effect. Is there an analogous effect for phonons? Are ther devices which convert phonon energy to electric ...
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Why does the creation operator take a continuum value for the momentum?
Imagine that you have a lattice and a set of masses. Each mass at a lattice point. Now each two neighbouring masses are connected with spring.
Now in Classical Mechanics (CM) the ground state is the ...
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Number density of LO and LA phonons as a function of temperature?
I'd like to know the how the number density of longitudinal optical (LO) and longitudinal acoustic (LA) phonons varies as a function of temperature of the material. Is there a simple expression for ...
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How to get an imaginary self energy?
The Lehman representation of the frequency-dependent single particle Green's function is
$$G(k,\omega) = \sum_n \frac{|c_k|^2}{\omega - E_n + i\eta}$$
where $n$ enumerates all the eigenstates of the ...
