Title :
May the linewidth be much narrower than transition probabilities?
Author :
Goun, A.A. ; Zel´dovich, B.Ya.
Author_Institution :
Sch. of Optics/CREOL, Univ. of Central Florida, Orlando, FL, USA
Abstract :
Summary form only given. Weisskopf-Wigner theory of radiative and collisional broadening gives for the linewidth /spl Gamma/ (HWHM): /spl Gamma//spl ges/(w/sub 1/+w/sub 2/)/2. Here w/sub 1/, w/sub 2/ are the decay probabilities for the levels 1,2. The easiest (albeit not quite rigorous) way to memorize (1) is to assume that the amplitudes c/sub 1/(t), c/sub 2/(t) of states 1 and 2 are decaying as exp(-w/sub 1/t/2), exp(-w/sub 2/t/2), and thus /spl rho//sub 21/= goes as exp(-/spl Gamma/t/2) with /spl Gamma/=(w/sub 1/+w/sub 2/)/2. Addition of any collisional phase shifts between levels 1 and 2 can only increase /spl Gamma/. This work answer the following question. Without assumption of any particular model of physical system, what are the ultimate limitations that follow from the non-negativity condition?.
Keywords :
atom-atom collisions; probability; quantum optics; spectral line narrowing; Weisskopf-Wigner theory; collisional broadening; collisional phase shifts; decay probabilities; linewidth narrowing; nonnegativity condition; transition probabilities; Absorption; Atom lasers; Atomic beams; Laser excitation; Laser transitions; Optical coupling; Optical pulses; Probes; Pulse measurements; Pump lasers;
Conference_Titel :
Quantum Electronics and Laser Science Conference, 2001. QELS '01. Technical Digest. Summaries of Papers Presented at the
Conference_Location :
Baltimore, MD, USA
Print_ISBN :
1-55752-663-X
DOI :
10.1109/QELS.2001.961906
