What is Photoluminescence: Definition and 11 Discussions

Photoluminescence (abbreviated as PL) is light emission from any form of matter after the absorption of photons (electromagnetic radiation). It is one of many forms of luminescence (light emission) and is initiated by photoexcitation (i.e. photons that excite electrons to a higher energy level in an atom), hence the prefix photo-. Following excitation various relaxation processes typically occur in which other photons are re-radiated. Time periods between absorption and emission may vary: ranging from short femtosecond-regime for emission involving free-carrier plasma in inorganic semiconductors up to milliseconds for Phosphorescence processes in molecular systems; and under special circumstances delay of emission may even span to minutes or hours.
Observation of photoluminescence at a certain energy can be viewed as an indication that an electron populated an excited state associated with this transition energy.
While this is generally true in atoms and similar systems, correlations and other more complex phenomena also act as sources for photoluminescence in many-body systems such as semiconductors. A theoretical approach to handle this is given by the semiconductor luminescence equations.

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  1. E

    Photoluminescence at lower temperature of carbazole

    Hello everyone, I deposit a thin film of HTM based carbazole and I measure the PL at lower tempertaure . by fiiting the experimental results with 5 peaks . I notice the dissapering of peak 1 at 300K and peak 3 at 200K. What is the nature of the interaction that can occur at lower temperature of...
  2. T

    A Incorrect Hybrid Polariton Dispersion Results

    I am trying to verify the results of the hybrid polariton case with the following hamiltonian, but cannot seem to verify the results in various published papers. Can someone please explain what is wrong and how to get the a similar dispersion graph? I'm solving for the eigenenergies for the...
  3. B

    I Spectrum of emission in photoluminescence

    hi, i did an experiment of photoluminescence in the lab and i was wondering about the spectrum of emission. why we get emission of photons with energies below the energy gap of the semiconductor? thanks
  4. Jalo

    I Photoluminescence Excitation (PLE) vs PL spectroscopy

    I'm not sure I understand what information we can get from Photoluminescence Excitation (PLE) that we don't get from regular PL. Let's imagine we have a sample with emissions between 700nm and 850nm. If I'm not mistaken in a typical PL experiment you'd just use a laser source with a wavelength...
  5. Benevito

    Photoluminescence at a heterojunction

    Do I understand it correctly that photoluminescence at a semiconductor heterojunction occurs because of intralayer recombination? If so, why can't photoluminescence occur because of interlayer recombination? Is it because momentum cannot be conserved in such a process ( like in the indirect gap...
  6. E

    Time resolved Photoluminescence analysis

    Currently we are working on gallium nitride material where I'm required to analyze the time resolved photoluminescence (PL) result. From literature review we found that many reported on lifetime decay value \tau so could anyone explain how to find this value. Does it come from the time resolved...
  7. S

    Photoluminescence experiment

    Greetings everyone, We have performed a photoluminescence experiment and plotted the resultant spectra for two samples of different concentration after correcting for the response of the CCD camera and got the results that is attached to this post. My question is that in the sample with...
  8. Y

    Relationship between photoluminescence intensity and Absroption Intensity

    I have measured photoluminescence (PL) and light absroption spectra of some transtion metal oxide nanostructures. The PL intensity increases remarkably by decreasing the size of nanostructures. However, the intensity of absorption vary litte. Is there any relationship between the PL intensity...
  9. A

    Photoluminescence vs Absorption

    Hi guys (and girls;)) I need your help... I really don't get the difference between a PhotoLuminescence and Absorption experiment. What kind of informations one can get from each experiment? Moreover, why generally photoluminescence experiments are carried on at low temperatures? Thanks...
  10. D

    Reference for photoluminescence data?

    I'm writing a lab report about the photoluminescence of two chemicals, (1) indocyanine green and (2) hexamethylindotricarbocyanine tetrafluoroborate. I've done the experiment, and now I need to (well, I've been advised to) find some data in a published paper or reference book to compare my...
  11. S

    Information on photoluminescence?

    Can anyone tell me any good websites which have information on photoluminescence? Also, i have an lcd projector with a light source which has about 500 lumens as the light intensity.If i need to project an image of an chess board on the lcd onto the screen with the best contrast say for a 32...