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Resistively and Capacitively Shunted Junction (RCSJ) Model of Josephson Junction Numerical Solution

For your simulation, it’s best to start from the dimensionless equation (slide 29): $$ \beta_c\ddot\delta+\dot\delta+\sin\delta=i+i_N \tag{1} $$ In your problem, $i$ is imposed (DC, additional ...
LPZ's user avatar
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Thermal Smearing in Josephson Junction

This might be a helpful reference to point you in the right direction, although not entirely sure. It discusses a Josephson junction simulation it appears: https://arxiv.org/pdf/1909.12421 A quote ...
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Why do we need to consider interaction for doping atom?

The ground (or any other) state of a donor impurity consisting of a localized center with a single positive elementary charge can only be occupied with a single electron with either spin up or down. ...
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Resistively and Capacitively Shunted Junction (RCSJ) Model of Josephson Junction Numerical Solution

First think about the point $U=0$. Any constant value of $\delta$ is a solution to the second equation. This means the current can take any value between $-I_0$ and $I_0$, as you see at $V=0$ in your ...
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Does diffusion current "consume" thermal energy?

There is no heating or cooling involved in the diffusion-drift currents in equilibrium. Essential is that at any electrical potential the electron ensemble is in thermal equilibrium with the crystal ...
freecharly's user avatar
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Does diffusion current "consume" thermal energy?

The charge carriers diffusing up the built-in field obtain a higher electrical potential energy; this energy has to come from somewhere, and it comes from charge carriers being driven down the built-...
Chemomechanics's user avatar
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Doping density dependence on effective density of states Si pn junction

At very high doping densities, the shown effective density of states formulae usually don't hold anymore because the wave functions of the discrete energy states close to the conduction or valence ...
freecharly's user avatar
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Connecting semi-conductors to outside wires

In semiconductor devices, electrical metal contacts are made that are called "ohmic contacts" with a very low (linear) resistance as opposed to the Schottky contacts with a very high non-...
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Connecting semi-conductors to outside wires

the chip and the chip carrier are connected for example with wire bonds consisting of a thin gold wire which is thermosonically welded to contact pads on each which do not constitute schottky ...
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C$_{60}$ fullerene electronic structure, C$_{60}$ insulator

The need to jump explanation is correct. With no half filled levels, the next energy level is a long way above the highest full level. Very few electrons will be in that level from thermal excitation. ...
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Intrinsic band gap vs work function of doped semiconductors

As you said, in a heavily n-doped semiconductor, the Fermi level $E_F$ is close to or a little above the conduction band edge $E_C$, but not very much. Conversely, in a heavily p-doped semiconductor, ...
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How exactly does a p-n junction operate when biased by current *not* voltage?

If you force a current through an (ideal) pn-junction diode with an ideal current source, you immediately obtain the corresponding voltage applied to the diode from the I-V characteristic of the diode....
freecharly's user avatar
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How exactly does a p-n junction operate when biased by current *not* voltage?

In the link you provide, there is the case you specificially are interested in: Forward biased conduction A current source can be thought of as voltage sources with a series resistor. Therefore, the ...
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Electromotive force by PN junction and extraneous role of electrolyte in electrochemical cells

You cannot use a pn-junction as a battery. Even though the n-side is at a higher electrical potential than the p-side due to the contact potential difference (called built-in voltage) of the n- and p-...
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Electromotive force by PN junction and extraneous role of electrolyte in electrochemical cells

The electrochemical reaction is a migration of positive ions through the battery from the negative to the positive side. Electrons flowing through the wire keeps the system neutral, allowing the ...
Claudio Saspinski's user avatar
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I don't really get transistors. How do they work exactly in the active region?

Reverse saturation current also flows through the collector-base junction, but the current due to additional injected electrons through the narrow base adds to it. In practical applications, the added ...
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When NPN collector is left open, does whole "collector" current flow out of the base?

When the collector is open and the emitter-base junction is forward biased, basically no net electron current will flow at the base-collector junction. This can only happen when the gradient of the ...
freecharly's user avatar
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Zener diode reverse bias I(V) equation

In principle, the current voltage characteristic of an ideal reverse bias Zener diode is determined by tunneling of electrons through the triangular energy barrier formed by the band gap and the large ...
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Drift current and diffusion current in depletion region of diode at equilibrium

The Shockley diode current-voltage relation assumes that both the total electron and the total hole current through the diode is determined by their diffusion currents at the respective edge of the ...
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Does the built-in potential inside a diode change by making bias?

The built-in potential of a pn-junction diode is defined as the internal potential difference over the depletion zone space charge region in thermal equilibrium. If you apply a reverse voltage, this ...
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Splitting of states in Semiconductor

The cited text gives a rough estimate of the exceedingly small energy spacing of quantum states in an energy band of a crystal. A factor of two for the spin doesn't make any difference here!
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Why are valence band and conduction bands parabolic in semiconductor physics?

In the semiconductors the behavior of the electrons in k-space near the minimum of the conduction band and near the maximum of the valence band are important because there at usual temperatures most ...
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In semiconductors, can distant particles in the same $k$-space recombine? Is this a wave phenomenon, ignoring physical separation?

No, this interference idea between electron and phonon wave is not correct. Interference occurs only between the same type of wave at the same frequency. For the recombination in an indirect ...
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Working of transistor

In the npn-transistor, you need a positive base-emitter voltage to inject the majority electrons of the emitter into the base, just like in a simple np-diode. (At zero base-emitter voltage, the np-...
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Basics regarding $k$-space axis and Energy graph in direct semiconductor

You are depicting the band diagram E(k) for an indirect semiconductor where the minimum of the conduction band in x-direction isn't at k=0 but at a finite k=kmin. Thus for k<kmin your E(k) ...
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