Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped Semiconductors
When a sample of semiconducting material is illuminated by monochromatic light, in which the photon energy is higher than the energy gap of the semiconductor, part of the absorbed electromagnetic energy is spent on the generation of pairs of quasi-free charge carriers that are bound by Coulomb attra...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-01-01
|
| Series: | Mathematics |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2227-7390/13/2/258 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832588061858332672 |
|---|---|
| author | Slobodanka Galovic Katarina Djordjevic Milica Dragas Dejan Milicevic Edin Suljovrujic |
| author_facet | Slobodanka Galovic Katarina Djordjevic Milica Dragas Dejan Milicevic Edin Suljovrujic |
| author_sort | Slobodanka Galovic |
| collection | DOAJ |
| description | When a sample of semiconducting material is illuminated by monochromatic light, in which the photon energy is higher than the energy gap of the semiconductor, part of the absorbed electromagnetic energy is spent on the generation of pairs of quasi-free charge carriers that are bound by Coulomb attraction. Photo-generated pairs diffuse through the material as a whole according to the density gradients established, carrying part of the excitation energy and charge through the semiconducting sample. This energy is indirectly transformed into heat, where the excess negatively charged electron recombines with a positively charged hole and causes additional local heating of the lattice. The dynamic of the photoexcited charge carrier is described by a non-linear partial differential equation of ambipolar diffusion. In moderate doped semiconductors with a low-level injection of charge carriers, ambipolar transport can be reduced to the linear parabolic partial differential equation for the transport of minority carriers. In this paper, we calculated the spectral function of the photoinduced charge carrier distribution based on an approximation of low-level injection. Using the calculated distribution and inverse Laplace transform, the dynamics of recombination photoinduced heat sources at the surfaces of semiconducting samples were studied for pulse optical excitations of very short and very long durations. It was shown that the photoexcited charge carriers affect semiconductor heating depending on the pulse duration, velocity of surface recombination, lifetime of charge carriers, and their diffusion coefficient. |
| format | Article |
| id | doaj-art-65bbc4a7dc1d4b8a858efa5f135d1e86 |
| institution | Kabale University |
| issn | 2227-7390 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Mathematics |
| spelling | doaj-art-65bbc4a7dc1d4b8a858efa5f135d1e862025-01-24T13:39:55ZengMDPI AGMathematics2227-73902025-01-0113225810.3390/math13020258Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped SemiconductorsSlobodanka Galovic0Katarina Djordjevic1Milica Dragas2Dejan Milicevic3Edin Suljovrujic4Vinca Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovica Alasa 12-14, P.O. Box 522, 11001 Belgrade, SerbiaVinca Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovica Alasa 12-14, P.O. Box 522, 11001 Belgrade, SerbiaFaculty of Philosophy, University of East Sarajevo, Vuka Karadžića 30, 71126 Lukavica, Republic of Srpska, Bosnia and HerzegovinaVinca Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovica Alasa 12-14, P.O. Box 522, 11001 Belgrade, SerbiaVinca Institute of Nuclear Sciences—National Institute of the Republic of Serbia, University of Belgrade, Mike Petrovica Alasa 12-14, P.O. Box 522, 11001 Belgrade, SerbiaWhen a sample of semiconducting material is illuminated by monochromatic light, in which the photon energy is higher than the energy gap of the semiconductor, part of the absorbed electromagnetic energy is spent on the generation of pairs of quasi-free charge carriers that are bound by Coulomb attraction. Photo-generated pairs diffuse through the material as a whole according to the density gradients established, carrying part of the excitation energy and charge through the semiconducting sample. This energy is indirectly transformed into heat, where the excess negatively charged electron recombines with a positively charged hole and causes additional local heating of the lattice. The dynamic of the photoexcited charge carrier is described by a non-linear partial differential equation of ambipolar diffusion. In moderate doped semiconductors with a low-level injection of charge carriers, ambipolar transport can be reduced to the linear parabolic partial differential equation for the transport of minority carriers. In this paper, we calculated the spectral function of the photoinduced charge carrier distribution based on an approximation of low-level injection. Using the calculated distribution and inverse Laplace transform, the dynamics of recombination photoinduced heat sources at the surfaces of semiconducting samples were studied for pulse optical excitations of very short and very long durations. It was shown that the photoexcited charge carriers affect semiconductor heating depending on the pulse duration, velocity of surface recombination, lifetime of charge carriers, and their diffusion coefficient.https://www.mdpi.com/2227-7390/13/2/258transport of chargeambipolar diffusionnon-linear dynamic problemlow-level injectionrecombination heat sourcesparabolic partial differential equation |
| spellingShingle | Slobodanka Galovic Katarina Djordjevic Milica Dragas Dejan Milicevic Edin Suljovrujic Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped Semiconductors Mathematics transport of charge ambipolar diffusion non-linear dynamic problem low-level injection recombination heat sources parabolic partial differential equation |
| title | Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped Semiconductors |
| title_full | Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped Semiconductors |
| title_fullStr | Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped Semiconductors |
| title_full_unstemmed | Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped Semiconductors |
| title_short | Dynamics of Photoinduced Charge Carrier and Photothermal Effect in Pulse-Illuminated Narrow Gap and Moderate Doped Semiconductors |
| title_sort | dynamics of photoinduced charge carrier and photothermal effect in pulse illuminated narrow gap and moderate doped semiconductors |
| topic | transport of charge ambipolar diffusion non-linear dynamic problem low-level injection recombination heat sources parabolic partial differential equation |
| url | https://www.mdpi.com/2227-7390/13/2/258 |
| work_keys_str_mv | AT slobodankagalovic dynamicsofphotoinducedchargecarrierandphotothermaleffectinpulseilluminatednarrowgapandmoderatedopedsemiconductors AT katarinadjordjevic dynamicsofphotoinducedchargecarrierandphotothermaleffectinpulseilluminatednarrowgapandmoderatedopedsemiconductors AT milicadragas dynamicsofphotoinducedchargecarrierandphotothermaleffectinpulseilluminatednarrowgapandmoderatedopedsemiconductors AT dejanmilicevic dynamicsofphotoinducedchargecarrierandphotothermaleffectinpulseilluminatednarrowgapandmoderatedopedsemiconductors AT edinsuljovrujic dynamicsofphotoinducedchargecarrierandphotothermaleffectinpulseilluminatednarrowgapandmoderatedopedsemiconductors |