Physical Review B, volume 18, issue 6, pages 2622-2631

Urbach's rule derived from thermal fluctuations in the band-gap energy

Publication typeJournal Article
Publication date1978-09-15
Quartile SCImago
Q1
Quartile WOS
Q2
Impact factor3.7
ISSN24699950, 24699969, 10980121, 1550235X
Abstract
The exponential absorption edge (known as Urbach's rule) observed in most materials is interpreted in terms of thermal fluctuations in the band-gap energy. The main contribution to the temperature shift of the band-gap energy is due to the temperature-dependent self-energies of the electrons and holes interacting with the phonons. Since the phonon number is fluctuating in thermal equilibrium, the band-gap energy is also fluctuating resulting in an exponential absorption tail below the average band-gap energy. These simple considerations are applied to derive Urbach's rule at high temperatures, while a simplified model with independent, noninteracting atoms is proposed to explain the behavior of Urbach's rule in the whole temperature range. The three parameters entering Urbach's rule are expressed in terms of parameters derived from the temperature shift of the band gap and from the exciton absorption. Comparison with experiments is performed for the II-VI compound ZnO. It is shown that a good agreement is found between the temperature shift of the exciton line observed experimentally and the temperature shift computed from the steepness parameter of Urbach's rule. The agreement with experimental values for the two other parameters is also satisfactory. It is shown that the band-gap shift (and absorption tail) in ZnO is caused by interaction with both acoustical and optical phonons. While the temperature-dependent polaron contribution can account for the optical-phonon contribution, the deformation-potential interaction with LA phonons is not sufficient to account for the acoustical-phonon contribution.

Top-30

Citations by journals

2
4
6
8
10
12
Journal of Applied Physics
12 publications, 6.98%
Physica B: Condensed Matter
12 publications, 6.98%
Physical Review B
10 publications, 5.81%
Physica Status Solidi (B): Basic Research
9 publications, 5.23%
Solid State Communications
6 publications, 3.49%
Journal of Non-Crystalline Solids
5 publications, 2.91%
Physics of the Solid State
5 publications, 2.91%
Applied Physics A: Materials Science and Processing
4 publications, 2.33%
Journal of Physics C Solid State Physics
4 publications, 2.33%
Journal of the Physical Society of Japan
3 publications, 1.74%
Journal of Materials Science
3 publications, 1.74%
Radiation Physics and Chemistry
3 publications, 1.74%
Journal Physics D: Applied Physics
3 publications, 1.74%
Journal of Physics and Chemistry of Solids
3 publications, 1.74%
Thin Solid Films
2 publications, 1.16%
Materials Science and Engineering B: Solid-State Materials for Advanced Technology
2 publications, 1.16%
MRS Proceedings
2 publications, 1.16%
Journal of Electronic Materials
2 publications, 1.16%
Surfaces and Interfaces
2 publications, 1.16%
Optical Materials
2 publications, 1.16%
Journal of Alloys and Compounds
2 publications, 1.16%
Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
2 publications, 1.16%
Solar Cells
2 publications, 1.16%
Physics Letters, Section A: General, Atomic and Solid State Physics
2 publications, 1.16%
Applied Surface Science
2 publications, 1.16%
Journal of Physical Chemistry C
2 publications, 1.16%
Ferroelectrics, Letters Section
2 publications, 1.16%
AIP Advances
2 publications, 1.16%
Nano Letters
1 publication, 0.58%
2
4
6
8
10
12

Citations by publishers

10
20
30
40
50
60
70
Elsevier
66 publications, 38.37%
American Institute of Physics (AIP)
16 publications, 9.3%
Springer Nature
15 publications, 8.72%
Wiley
14 publications, 8.14%
American Physical Society (APS)
11 publications, 6.4%
IOP Publishing
10 publications, 5.81%
Pleiades Publishing
7 publications, 4.07%
American Chemical Society (ACS)
5 publications, 2.91%
Taylor & Francis
5 publications, 2.91%
Physical Society of Japan
3 publications, 1.74%
Materials Research Society
2 publications, 1.16%
Japan Society of Applied Physics
2 publications, 1.16%
World Scientific
1 publication, 0.58%
Cambridge University Press
1 publication, 0.58%
Multidisciplinary Digital Publishing Institute (MDPI)
1 publication, 0.58%
Science in China Press
1 publication, 0.58%
China University of Geosciences (Beijing) and Peking University
1 publication, 0.58%
Royal Society of Chemistry (RSC)
1 publication, 0.58%
IEEE
1 publication, 0.58%
Optical Society of America
1 publication, 0.58%
National Academy of Sciences of Ukraine - Institute of Semiconductor Physics
1 publication, 0.58%
Autonomous Non-profit Organization Editorial Board of the journal Uspekhi Khimii
1 publication, 0.58%
10
20
30
40
50
60
70
  • We do not take into account publications without a DOI.
  • Statistics recalculated only for publications connected to researchers, organizations and labs registered on the platform.
  • Statistics recalculated weekly.

Are you a researcher?

Create a profile to get free access to personal recommendations for colleagues and new articles.
Metrics
Share
Cite this
GOST |
Cite this
GOST Copy
Skettrup T. Urbach's rule derived from thermal fluctuations in the band-gap energy // Physical Review B. 1978. Vol. 18. No. 6. pp. 2622-2631.
GOST all authors (up to 50) Copy
Skettrup T. Urbach's rule derived from thermal fluctuations in the band-gap energy // Physical Review B. 1978. Vol. 18. No. 6. pp. 2622-2631.
RIS |
Cite this
RIS Copy
TY - JOUR
DO - 10.1103/PhysRevB.18.2622
UR - https://doi.org/10.1103/PhysRevB.18.2622
TI - Urbach's rule derived from thermal fluctuations in the band-gap energy
T2 - Physical Review B
AU - Skettrup, T.
PY - 1978
DA - 1978/09/15 00:00:00
PB - American Physical Society (APS)
SP - 2622-2631
IS - 6
VL - 18
SN - 2469-9950
SN - 2469-9969
SN - 1098-0121
SN - 1550-235X
ER -
BibTex |
Cite this
BibTex Copy
@article{1978_Skettrup,
author = {T. Skettrup},
title = {Urbach's rule derived from thermal fluctuations in the band-gap energy},
journal = {Physical Review B},
year = {1978},
volume = {18},
publisher = {American Physical Society (APS)},
month = {sep},
url = {https://doi.org/10.1103/PhysRevB.18.2622},
number = {6},
pages = {2622--2631},
doi = {10.1103/PhysRevB.18.2622}
}
MLA
Cite this
MLA Copy
Skettrup, T.. “Urbach's rule derived from thermal fluctuations in the band-gap energy.” Physical Review B, vol. 18, no. 6, Sep. 1978, pp. 2622-2631. https://doi.org/10.1103/PhysRevB.18.2622.
Found error?