Questions tagged [hall-effect]
The Hall effect is a voltage arising from an electric field perpendicular to a magnetic field in a material. It is to be distinguished from the quantum hall effect (QHE).
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Hall effect source impedance
Background
I am an electrical engineer. My friend is a technician in a physics lab and he is using an electromagnetic flow meter (i.e. magmeter) which relies on the Hall effect to measure the flow ...
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About the relationship between Hall coefficient and carrier concentration
I had a question while studying the Hall effect.
After going through various intermediate processes, the Hall coefficient can be derived as follows,
$R_H=\frac{1}{qn},$
where $q$ is the quantity of ...
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Please explain Hall effect in p type semiconductors without the use of holes [closed]
The movement of holes means the movement of electrons in opposite direction, so in Hall Effect the particles on which force is applied finally must be electrons, so there must be no positive charge ...
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Why force by electric field is appearing?
I want to ask about the Hall effect. Why is the force by the electric field appearing?
I can understand the appearance of the Lorentz force. However, I do not know for what reason the force due to the ...
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What is the correct type of the Berry curvature?
I am studying Berry curvature for a specific material and faced different types of the Berry curvature formula. Some papers use only valence eigenstates (u1) like this $$i*(<(∂U1/∂kx)| (∂U1/∂ky)>...
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How can we tell if we have ordinary or anomalous Hall conductivity?
Based on the Hall optical conductivity graph, how can we tell if we have ordinary or anomalous Hall conductivity?
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How to separate electron and hole mobilities in a intrinsic semiconductor?
I read in textbooks that the electric conductivity of a semiconductor is $\sigma=q(n\mu_n+p\mu_p)$, where $q$ is an electron's charge, $n$ and $p$ are the concentrations of electrons and holes, $\mu_n$...
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Hall voltage vs frame dependent electric field in conductor
The hall voltage is created by a current in a magnetic field.
Similarly, a non current carrying conductor in an electric and magnetic field will appear to have a voltage in a different reverence frame....
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Can one Short a Hall Bar?
Consider a classical Hall bar, no quantum effects. If a magnetic field is applied the standard undergraduate treatment tells us that the Lorentz Force will lead to a build up of excess charge on one ...
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Classical and quantum Hall effects
I am trying to understand the hall effects and have a few problems with them.
So let's consider the classical Hall effect. We know that we consider a sample, where the electrons flow, we apply the ...
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Quantum Hall effect diverges at $B=0$
In the integer quantum Hall effect, with the applied magnetic field reduced, more and more LLs get filled and one can observe higher and higher plateaus in the Hall conductivity $\sigma_H(B)$. ...
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Variation of Current In The Hall Effect Experiment
As a 12th Grader, our class came across a very simple setup of the Hall Effect Experiment during our course on Electromagnetism. The entire idea and eventual steady state conditions all make perfect ...
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Electric field shielding by a metal plate
I was watching this video on Hall effect, and to demonstrate that it is not electric fields that are bending the electron beam, the presenter puts a metal plate between the magnet and the beam.
So, my ...
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Impact of thickness of metal on hall effect
I was reading the paper on the Hall Effect and found that the initial experiment was performed on a metal strip. The experiment on the metal failed to provide any useful results, and then it was ...
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Is diamagnetic part of conductivity always longitudinal/diagonal?
The Kubo formula for linear response is given as $$\sigma_{ab}(\omega)=\frac{i}{\omega}[\Pi_{ab}(\omega)-\Pi_{ab}(\omega=0)]$$ with $\Pi$ the current-current correlation. It is often claimed that the ...
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Hall Effect on a spiral [closed]
A flat spiral in immersed in a homogeneous magnetic field. An electric current is flowing in the spiral. The directions of the B field, the spiral and the current can be seen in the picture. As the ...
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All closed orbits in semiclassical model
I'm studying from "Solid State Physics" by Ashcroft-Mermin. In particular, in chapter 12 it talks about the semiclassical model and tries to reason about the Hall effect in the limiting case ...
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Is current density independent of applied fields for Bloch electrons?
Following Ashcroft-Mermin chapter 12 the semiclassical dynamics is governed by
$
\dot{\vec{r}} = \vec{v}_n(\vec{k}) = \frac{1}{\hbar}\frac{\partial \epsilon_n(\vec{k})}{\partial \vec{k}}
$
and
$
\hbar ...
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Hall effect of Metal and Semiconductor [duplicate]
I am pretty much confused in the topic of Hall effect, as it is discussed in Metals and Semiconductor. My question is -
Hall effect in Metals is due to electron as they are in majority, so hall ...
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Shubnikov-de-Haas effect and Quantum Hall effect
I am wondering if these two phenomena are two names for the same thing or whether these are distinct effects and there are situation where one appears, but the other one doesn't?
Both seem to produce ...
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Why does the presence of magnetoresistive effects indicate the existence of multiple types of charge carriers in a material?
I am currently enrolled in a solid state physics course, and have just completed a lecture on the Hall effect, though it did not go into too much detail. It was mentioned that with van der pauw ...
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Hall effect in a conducting ring
Consider a conducting ring moving through a uniform magnetic field of magnitude $B$, with speed $v$. To visualise, suppose the magnetic field is directed out of the page and the ring is moving ...
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Can you measure hall voltage for holes and electrons in the same time?
I have an experiment on hall effect, and the goal is to determine hall coefficient and determine what type of the material it is, using Uh=f(B) graph. The table of results show two columns of measure ...
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Hall sensor for electric(!) field?
Is it (in principle) possible to measure the strength of an electic(!) field with a hall sensor?
I think so, for the following reasons:
The hall sensor is a conductor. If we place an conductor in an ...
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Hall effect for a magnet falling through a copper pipe?
A falling magnet in a copper pipe exerts a Lorentz force on the electrons that participate in the eddy currents a and b. I mean the vertical magnetic force $F = Bqv$, denoted by the blue arrows in the ...
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Why are the plateaus in the Quantum Hall horizontal rather than diagonal
I was wondering why the plateaus of $\rho_{xy}$ in the integer quantum Hall effect are horizontal and do not scale linearly with the magnetic field $B$ since the Lorentz force should still be acting ...
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Hall effect: Do the charges that build up on the sides of conductor kept in uniform magnetic field get uniformly distributed?
When we keep a metal block through which some constant current is flowing in a uniform magnetic field the charges will separate and a potential difference will be created b/w the sides of the ...
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Does a current carrying conductor carry a net total charge or only a net bulk charge?
I would like to start a discussion in which we have an ongoing debate elsewhere with no convincing solution in sight. So I decide to ask here:
The question is mainly academic: Is a current carrying ...
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How does the conductivities of metals and semiconductors vary when placed in the presence of magnetic field?
Suppose you have two materials one is a metal and other is a heavily doped semiconductor and they are placed in a magnetic field. What experiment will you do to distinguish between them? Does the ...
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What does it mean to say that the majority carriers are holes?
Even when there are holes, the holes move only because electrons are jumping from one hole to the next. So why doesn't it make sense to say that electrons are the majority carriers in p-type ...
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How to calculate the surface charge density of a conducting plate moving at constant speed in a uniform magnetic Field [closed]
I have conducting plate moving at velocity $v = 6.28\cdot10^5\mathrm m/\mathrm s$ through a uniform magnetic Field of $B = 0.18\mathrm T$. How can I determine the surface charge density?
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The mechanism behind the Lorentz force [duplicate]
It has been known for 130 years that a moving electron entering an external magnetic field is deflected (Lorentz force, Hall effects, synchrotrons). What I have never read is a description of how this ...
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Why doesn't the classical model of electrical conduction work with iron, cadmium and bismuth?
My textbook says this:
In most metals, the charge carriers are electrons and the charge - carrier density determined from Hall - effect measurements is in good agreement with calculated values for ...
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Analogous to hall effect, does electric field applied perpendicular to the current direction through a semiconductor bar create magnetic field?
Hall effect says, when a magnetic field is applied perpendicular to current direction in a semiconductor bar, an electric field (and hence Hall voltage) will be created across the side which is ...
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Longitudinal conductivity from density of states (DOS)
It is well-known that using the so-called Streda formula, the transversal conductivity $\sigma_{xy}$ and thus the Hall conductivity in a two-dimensional material is given as the derivative of the ...
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Why is magneto-resistance not possible classically?
Someone recently asked me this question and I don't know why we can't talk about magnetoresistance in the classical picture. As we know that magnetoresistance is the tendency of a material (often ...
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Computing a second harmonic resistance out of a wave-like resistance signal
I want to reproduce the results of a paper, in which they measure the Anharmonic Hall Effect (AHE) resistance $R_{AHE}^{2\omega}$. There are several protocols for measuring it experimentally, but I'm ...
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Relationship between the magnetic dipole of the electron and the polarisation of its radiation
When passing through a magnetic field, electrons are deflected sideways. This is the basis of the Lorentz force and all Hall effects. If this is done on a larger scale in particle accelerators or, in ...
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How do protons and electrons separate across a conductor in the Hall Effect, if protons "don't move"?
I have a (probably very) basic understanding of electricity, how/why current flows, etc. from my ham technician's license. I often think of the water-in-a-hose analogy, how pressure (voltage?) causes ...
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How to calculate the total charge separated by the Hall effect?
If a plate is undergoing the Hall Effect, how can we calculate the total charge $Q$ present on either side of the plate at the equilibrium state?
And how can we calculate the force that such a charge ...
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Do I correctly understand the reason why the Hall resistivity in Quantum Hall Effect becomes larger as magnetic field increases?
I'm wondering whether I correctly understand the increase of the Hall resistivity rho_xy in Quantum Hall effect.
As you can see the graph,
As magnetic field becomes much larger, the quantization of ...
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Why (intuitively) do more charge carriers result in a smaller Hall effect?
From the equation for the Hall effect:
$$\Delta V_H= \frac{I B}{n q t}$$
[Where $I$ is the current, $B$ the electric field magnitude, $n$ the density of charge carriers, $q$ the charge per charge ...
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Why does Equilibrium produce voltage difference in Hall Effect?
This question is bothering me ever since I studied Hall effect. Am I probably missing out a point?
To elaborate the question: I understand that Lorentz force and electric force are equal and opposite ...
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How to make sense of the side jump mechanism for anomalous Hall effect?
According to this paper, https://doi.org/10.1103/PhysRevB.2.4559, the electron (wave packet), moving along $x$ axis, undergoes a transverse shift $Δy$ after collision with spin-orbit coupling center. ...
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Calibration of Hall Effect Measurement using Standard Reference Material (NIST)
I would like to calibrate a low-temperature Hall effect measurement using a Fe SRM.
Are there any standardized Hall measurements of SRM's available?
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How to know a semiconductor is p type or n type from hall effect calculations? [closed]
Using the hall effect calculations how can we determine a semiconductor is p type or n type
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How can we explain that beryllium has positive charge carriers as a metal (from Feynman Lectures)?
This question naturally arises from reading Feynman Lectures Vol III 14-3 The Hall effect, online available here, where Feynman states the following:
The original discovery of the anomalous sign of ...
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How to understand the linear relation between Fermi level $E_F$ and the length $L$ of the slab in Hall effect and spin Hall effect?
I am following this paper to learn the physics of the spin Hall effect. Unlike the conventional Hall effect, the role of the external magnetic field $\vec{B}$ has been replaced by the effective ...
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What is meant by compensating the Hall Voltage?
We're doing an experiment to measure the Hall Voltage as functions of current and magnetic field, and we're meant to Compensate the Hall Voltage for $B=0T$. What does this mean, and why do we do it?
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Spin Hall effect
I am trying to understand the paper by Dyakonov and Perel (1971) "Possibility of orienting electron spins with current", but cannot see how they obtain the phenomenological equations for spin density ...
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