Spectral narrowing induced by discrete frequency fluctuations

Yoav Sagi, Rami Pugatch, Ido Almog, Nir Davidson

Research output: Chapter in Book/Report/Conference proceedingConference contribution


We study an ensemble of two level systems coupled to an environment that randomly modulates their resonant frequency. We use Poissonian statistics for the random frequency jumps and derive a closed-from formula for the spectrum in terms of the inhomogeneous frequency distribution and the Poisson rate constant. We show that for a Gaussian distribution our result asymptotically reproduces the results of the well known Kubo model. Our formula holds for any frequency distribution. In particular we calculate the spectrum of atoms in a 3D trap harmonic trap and show that motional narrowing naturally emerges. We experimentally measure this spectrum with optically trapped ^87Rb atoms and obtain a good agreement to our theory without fitting parameters. Our theory apply to a wide range of systems such as atomic ensembles, nuclear magnetic resonance spectroscopy, single molecule spectroscopy and the line-shape of lasers.
Original languageEnglish GB
Title of host publication41st Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics
StatePublished - 2010

Publication series

NameAmerican Physical Society, 41st Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics Volume 55, Number 5, March 25-29, 2010


Dive into the research topics of 'Spectral narrowing induced by discrete frequency fluctuations'. Together they form a unique fingerprint.

Cite this