Questions tagged [photoelectric-effect]
The observed behavior in which light falling on certain metals can eject electrons from the surface.
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Factors determining Saturation Current in Photoelectric effect
Ive understood that the saturation current is the current obtained in a photoelectric experiment when all the photo electrons emitted at the cathode are able to pass through the repulsive space charge ...
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Changing frequency of light without changing its energy
Three observations were detected in the photo-electric effect:
The kinetic energy of the ejected electrons doesn't change if you change the intensity of light (instead more electrons are ejected with ...
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Quantum efficiency and relative response of a photodetector
by looking at those two graphs from the same CMOS sensor (Sony IMX 533), one monochromatic and one with a colour filter array (CFA), I was wondering why the monochrome sensor is expressed as absolute ...
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Is it possible for photons to have different energy and same momenta if they are emitted by bichromatic light source in all directions?
Suppose photons are emitted by a bichomatics source of light in all directions. Is it possible that two photons are present having different energy but same momenta ?
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In the photoelectric effect experiment shown in the figure down below, Does the galvanometer only read the photocurrent?
Does the galvanometer read the photocurrent only or charges in the native conductor take part in as well?
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Can heat be used to create charge carriers in the depletion region of a pn junction as is done by light with the photoelectric effect?
I have watched some videos on how Photovoltaic cells produce electricity and it seems to be by the production of charge carriers in the depletion region due to the photoelectric efect which are then ...
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What happens to the kinetic energy an electron gains from absorbing a photon with more energy than the bandgap?
For context, I'm taking a course on quantum mechanics geared towards electrical engineering majors (so basically the standard curriculum, but with additional focus on EE applications, particularly in ...
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Cause non-linear relation between intensity and photo-current
I wanted to investigate and validate the relationship between intensity and photo-current with a simple experimental setup. I expected a linear relationship based on the photo-diode's datasheet (I've ...
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What actually causes the electromagnetic field to be quantized?
My understanding is that quantization in QM is because the wavefunctions are analogous to classical standing waves, where the boundary conditions determine the specific quantization. That's how it ...
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Confusion about work function and Fermi energy
The work function $\Phi$ is the amount of energy required to move an electron from a state where it is at Fermi energy $E_f$ in the bulk of a metal to a state where it is at rest at a point just ...
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Difference between photodiodes and avalanche photodiodes
I'd say I'm quite aware of how avalanche photodiodes work but I'm unsure of how usual photodiodes work respectively how they differ from each other.
Let's bring it down to: APDs are able to detect ...
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On a PV cell, why do electrons travel through the copper rather than through the PN junction?
thank you all for reading me!
I am currently reviewing the structure and working principles of a PV cell. I think I understand the following steps about how the PN junction is formed and what happens ...
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Is household alluminium foil good for observing photoelectric effect?
I have built an electroscope(very primitive, just a wire and some aluminum foil). I'm thinking about using it to observe the photoelectric effect. But I don't have any high frequency wave producing ...
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Can phonons experience a photoelectric-like effect? [closed]
In a crystal lattice, could phonons experience some form of the photoelectric effect?
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Wavelength of electron during photoelectric effect
Consider light of sufficiently enough wavelength not only to remove the electron from metal but also to provide it kinetic energy
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Now my question is :
If the wavelength of light is Lambda, is the ...
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Photoelectric current dependency on frequency of incident light [duplicate]
I recently came across a doubt in the photoelectric effects topic, and It wasn't cleared even after researching,
The doubt is, that when we increase the frequency of incident rays, current is ...
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Current in Photoelectric effect
Experimentally, the current is saturated at negative values when reaching the stopping potential (as in the first photo) Theoretically, current is saturated at zero (as in second graph) why is that?
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The impact of electron density on photoelectric effect
I'm a second year radtion therapy student and i'm looking at the attentuation of KV energy beams. I'm wondering why for the photoelectric effect to occur does there need to be a high amount of 'inner'/...
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Why does a photon can only be absorbed by an electron if the energy of the photon equals to the energy difference between two energy level levels?
As my title suggests, I am a bit confused as in why does a photon require exactly amount of energy in order to be absorbed by an electron? What will happen if the photon has more energy than the ...
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Relationship between power band in frequency band of oscillating light and that frequency [closed]
If one shines a light on an electrode, the electrode has a change in voltage due to the photoelectric effect. Thus, if one shines a light whose luminance oscillates sinuosidally with time, the voltage ...
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Compton absorption vs Compton scattering
I'm reading Knoll's book "Radiation Detection and Measurement", and in the chapter discussing the interactions between gamma radiation and matter, he explains about the three main types of ...
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Could the saturation current last forever? (Photoelectric effect)
It is understood that the saturation current is achieved when the potential difference across the emitting and collecting plate allow for the rate of photoelectric emissions to equal the rate of ...
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Radiation pressure and photoelectric effect
Imagine an experiment where there is a propeller and a laser that shines on this propeller.
The propeller will rotate due to the radiation pressure from the laser
This radiation pressure is dependant ...
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Hallwachs’ and Lenard’s Experiment: why is kinetic energy simply $KE_{max}=eV$ where V is the potential difference
Hallwachs’ and Lenard’s Experiment: why is kinetic energy simply $KE_{max}=eV$ where V is the potential difference?
As the photoelectron is usually ejected by light, why shouldn't it be $h(v-v_o)+eV$ ...
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Why is saturation current a function of intensity?
I know from this question that a saturation point exists because beyond a certain point no more electrons can be emitted beyond a point due to the accumulation of charges, if this is the case, why ...
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If $I = naevd$ where $v$ is the drift velocity then why in photoelectric effect increase potential across plates only increase current for a while?
Just studying photoelectric effect and got this confusion.
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Photoemission - A surface process?
The square law of Fowler for photoemission into a vacuum is based on the assumption that the photoelectron current is proportional to the number of electrons available in the metal per unit volume ...
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Why do silicon photodiodes respond to a wavelength range of 190-1100nm?
Silicon photodiodes respond to a wavelength range of around 190-1100nm (source: wikipedia). I understand that photodiodes function by having a photon of sufficient energy create an electron-hole pair ...
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Can photomultiplier measure energy of incident photon?
When using a photomultiplier tube, can one obtain a precise energy of photon entering the tube? Can we control number of electrons emitted from each dynode? As far a I know, this is statistical ...
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Questions about Quantum theory of light
I'm an electrical engineer and this my first course about modern physics.
In quantum theory of light, Einstein proposed that the light has a particle property and each photon has an energy equal to
$E=...
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Accumulation of electrons inside vacuum tube during photoelectric effect
I'm thinking of the general photoelectric effect experiment set-up.
We know that after certain value of potential difference between Cathode and Anode, the photocurrent of the circuit will reach ...
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How can an electron fully absorb a photon in the photoelectric effect?
I made a scenario where a photon with energy and momentum $(E,p)$ hits an electron with mass $m$, and the electron absorbs the photon and got a contradiction. This implies that this scenario is ...
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Does the photocurrent depend on the frequency?
I've read many posts and textbooks on modern physics and quantum mechanics but none seem to explain this very well. Some say that it doesn't depend on the frequency of the photons, for a reason ...
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A conceptual doubt regarding photoelectric effect
The circuit diagram to determine the stopping potential $V_s$ is shown.
Suppose photons of energy $h\nu$ are incident on the emitter plate having work function $\phi$. Then, the maximum kinetic energy ...
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Why doesn't the saturation photoelectric current depend on frequency?
From my understanding, even if the frequency of a photon is above the threshold frequency, it is not necessary that an electron gets ejected as the photon may have been absorbed by a metal atom ...
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Stopping potential and EM radiation
I'm a little confused about something
We know from the photoelectric effect, that when a beam of light falls on the surface of a metal with very low ionization energy, electrons get ejected, one way ...
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If an atom has 'infinite energy levels', how does the photoelectric effect exist?
I don't quite get claims that an atom has 'infinite energy levels'. The photo-electric effect tells us that if photons of a certain threshold of energy are absorbed, the electrons will be freed from ...
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Photoelectrons travel with various KE
I learned that in the photoelectric effect experiment, an electron would possess maximum kinetic energy $KE_{max}=e{V_s}$, where $V_s$ is the stopping potential, that is equal to the photon energy it ...
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How did Einstein calculate the wavelength of photons?
Einstein's Photoelectric equation states that
$$h\nu = h\nu_0 + \frac{1}{2}mv^2$$
which uses frequency. But if he assumed light to be a stream of particles how would he calculate it's frequency? de ...
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Phototcurrent illuminated gold plate
Let's say we have a gold plate connected to a current meter and illuminate the plate. How would you calculate the photo current?
My first idea was to check the ionization energy of gold $E_{ion}$ and ...
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Recreating Millikan's Photoelectric Experiment
I am designing a set-up to recreate Millikan’s Photoelectric Experiment, which is similar to all the standard online simulations. I hope to achieve this without using a vacuum as it is very expensive ...
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Why electron do not eject out even when there is photon of less threshold energy with increasing in time [duplicate]
When photon having certain energy less than threshold energy strikes on the electron of metallic plate. Electron do not eject out. But my question is when photon are falling continuously then ...
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CCD potential well depth
For a while I've been curious about the design of charge coupled devices. All I can find about CCDs is more of a popular science junk that explains the operation principles but doesn't give any models ...
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Diffrence between thermionic emission and photoelectric emission
Thermionic emission involves heat energy to excite the electron and remove it. In the photoelectric effect, a beam of light is involved.
As per my understanding heat and photons, both are energy. Heat ...
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Does photoelectric effect occur at stopping potential?
By applying stopping potential, does the photoelectric effect cease to occur or does the photoelectric effect occur and the electron does get emitted and with zero kinetic energy?
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How does the photoelectric effect coincide with thermionic emission and the particle nature of light?
I was watching a video explaining how the photoelectric effect shows the particle like nature of light. my understanding is that the frequency of the light determines the amount of energy delivered to ...
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Photon-Atom Interaction: Atomic Spectrum vs Photoelectric Effect
Apologize if the question is elementary or already asked (not aware of it).
Far as I understand:
Ground state electrons in atom can only absorb photons of certain (discrete set of) energies to jump ...
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How is the law of conservation of energy satisfied in a photoelectric cell?
In a battery-driven circuit, the current produced is of such a value that the power delivered by the battery (VI) is equal to the power dissipated in the resistance (I^2*R). If the resistance changes, ...
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Where does energy in a photo-emissive cell come from?
According to most textbooks, photo-electrons are attracted to a positively charged electrode (by connecting it to the positive terminal of a battery). If this is the case, then what is the practical ...
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What would happen if I were to shine light on a metal for a long time?
According to photoelectric effect, shining light of sufficient energy would ionized an electron from a metal.
So what would happen if I were to shine a light on the metal for a very long time?
Will ...
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