Sadegh, Sanaz, authorBarkai, Eli, authorKrapf, Diego, authorIOP Publishing Ltd., publisher2007-01-032007-01-032014-11Sadegh, Sanaz, Eli Barkai, and Diego Krapf, 1/f Noise for Intermittent Quantum Dots Exhibits Nonstationarity and Critical Exponents. New Journal of Physics 16, no. 11 (November 2014): 1-15. http://dx.doi.org/10.1088/1367-2630/16/11/113054http://hdl.handle.net/10217/88130The power spectrum of quantum dot (QD) fluorescence exhibits 1/ƒ β noise, related to the intermittency of these nanosystems. As in other systems exhibiting 1/ƒ noise, this power spectrum is not integrable at low frequencies, which appears to imply infinite total power. We report measurements of individual QDs that address this long-standing paradox. We find that the level of 1/ƒ β noise decays with the observation time. The change of the spectrum with time places a bound on the total power. These observations are in stark contrast with most measurements of noise in macroscopic systems which do not exhibit any evidence for non-stationarity. We show that the traditional description of the power spectrum with a single exponent β is incomplete and three additional critical exponents characterize the dependence on experimental time.born digitalarticlesengnanocrystals1/ƒ noisepower spectrumblinkingTextThis article is open access and distributed under the terms and conditions of the Creative Commons Attribution 3.0 Unported (CC BY 3.0).https://dx.doi.org/10.1088/1367-2630/16/11/113054