Photonics Encyclopedy

Photonics Encyclopedy or RP - Photonics Encyclopedy is website that promotes the consulting service for the Laser and Photonics Industry belobging to Dr.R.Paschotta [http://www.rp-photonics.com , URL of the encyclopedy.] . The declared "Open Access" allows only reading, therefore some articles may be out of date.

Possible confusion

Some definitions suggested in this encyclopedy are different from those used in scientific journals.

For example, the quantum defect is defined as "ratio of laser to pump photon energy" [http://www.rp-photonics.com/quantum_defect.html , definition of quantum defect in theRP-Photonics Ensyclopedy] .According to this definition, the higher is quantum defect, the higher efficiency is achievable; at small quantum defect, the efficiency is low.In the scientific literature, the quantum defect is defined as difference between pump and laser photon energiescite journal
url=http://ieeexplore.ieee.org/xpls/abs_all.jsp?isnumber=6035&arnumber=234394&count=87&index=4
author=T.Y.Fan
coauthors=
title=Heat generation in Nd:YAG and Yb:YAG
journal=IEEE Journal of Quantum Electronics
volume=29
pages=1457–1459
year=1993
doi=10.1109/3.234394] . According to this definition, higer is quantum defect, the higher efficiency of laser action can be acheieved.

In addition, the termin quantum defect may refer also to the a correction applied to the equations governing Rydberg atom behavior to take into account the fact that the inner electrons do not entirely screen their associated charge in the nucleus [http://www.phy.davidson.edu/StuHome/joesten/IntLab/final/rydberg.htm ,Rydberg Atoms and the Quantum Defect at the site of Davidson College, Physics department] .

References