All Questions
Tagged with semiconductor-physics condensed-matter
168
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Is spin relaxation asymmetric in magnetic semiconductors?
I am considering photo-excitation in magnetic semiconductors (e.g. metal organic frameworks). The cartoon picture is like this:
where there will be a spin polarization in the conduction band since ...
- 203
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42
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How can red LEDs still give a faint glow at a voltage of only 1.4V? [duplicate]
How can a red LED work at a voltage of only $1.4{\rm V}$? Red photons have an energy of $1.77{\rm V}$ if we use $\lambda = 0.7\mu\text{m}$ in the relation:
$$ E = \hbar \omega = \frac{2\pi\hbar c}{\...
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Where can I read about excitons?
I'm having a tough time finding a good reference for excitons. I know next to nothing about them, and I'd like to find a good book/paper/notes that would introduce it in a slow, pedagogical way. ...
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How to determine the effective mass for multivariate dispersion relation? [duplicate]
Consider the 1D dispersion obtained by the tight-binding method:
$
E(k)=\epsilon_0-t\cos(ka)
$
$\epsilon_0$ is the on-site energy and $t$ is the hopping energy. To find the effective mass, you can ...
- 43
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102
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Definition of Hall's current
Dear fellow physicists!
I come to you with a question regarding the definiton of the Hall current.
The only sentence close to definition of this concept, I have found after extensive search on the ...
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Can a DC voltage excite a pure semiconductor (or insulator) from the valence band to the conduction band?
I have a question I am sticking around and can't find a satisfying answer. Say I have an intrinsic semidonductor at zero Kelvin (no electrons in conduction band). I apply a DC voltage across it. Can ...
- 21
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Interpretation of velocity in the de Broglie wavelength of an electron in a crystal
The de Broglie wavelength of a free electron is $\lambda = h/mv$ whre m is the free electron mass, and v is the velocity. Often in introductory solid state physics literature (review articles, lower-...
- 116
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$\mathbf k\cdot\mathbf p$ Hamiltonian
I am looking into the $k\cdot p$ Hamiltonian approach to describe a semiconductor system. The simplest system appears to be the 2x2 system which can be visualised as: \begin{pmatrix}
\epsilon(k) &&...
- 155
2
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39
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Extension from Excitons to Trions
I am curious about the fundamentals of how a trion state is defined. An exciton state is considered a bound electron-hole pair. This can be formed by is we have a ground state which consists of a full ...
- 155
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Where can I read about Valleytronics?
Where can I read about Valleytronics? Are there any good books or review papers on this topic? And which are the most influential papers?
The question was also posted at the Matter Modeling site.
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$\vec{k}\cdot\vec{p}$ Hamiltonian approach
I am new to reading into the $\vec{k}\cdot\vec{p}$ approach.
Where for a periodic function $u_{\vec{k}}$, which satisfies the Schrodinger equation:
$$
H_\vec{k}u_{\vec{k}}=E_{\vec{k}}u_{\vec{k}}
$$
...
- 31
3
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219
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What is the mechanism of the giant Stark effect?
I do not understand why the band gap shrinks due to the giant Stark effect.
In semiconductors such as black phosphorus, it has been confirmed that the band gap shrinks due to a dc electric field. This ...
- 67
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139
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Integral of diverging function
I'm reading the chapter 10 on excitons of "Quantum Theory of Optical and Electronic Properties of Semiconductors" by Hartmut Haug and and Stephan W. Koch. In the second section of this ...
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Why is there a linear relationship between the output frequency of a laser diode and the voltage applied to it?
I'm using a tunable laser diode in an undergraduate Rb SAS （saturated absorption spectroscopy） experiment. The product I'm using is the Toptica DLC DL pro, links down below (not an ad). The frequency ...
- 619
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181
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How can the Fermi Level cut the Conduction Band (in a doped Semiconductor)?
Let’s say we have an intrinsic, undoped semiconductor. The Fermi level will then be in the middle of the band gap between conduction and valence band.
Now let’s introduce n-doping to the system. In ...
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