You can find an elaborated summary of QUEST research activities in a "PTB Mitteilungen" - Magazine, 
Special Issue Vol.119 (2009), No.2
A brief review of our research tasks and some recent results achieved in our groups you can find in the following positions:
"Quantum Sensors with Cold Ions", J. Keller, K.Pyka, N.Herschbach, T.E. Mehlstäubler, Poster presentation, IFCS, Newport Beach, June 2010.
"Optical Clocks and Frequency Standards - present research at PTB", T.E. Mehlstäubler, Ch. Lisdat, J.S.R. Vellore Winfred, T. Legero, F. Riehle, U. Sterr, H. Schnatz, G. Grosche, B. Lipphardt, B. Stein, I. Sherstov, Ch. Tamm, E. Peik - Poster presentation, BIPM Metrology Summer School 2008, 29 June 2008
"Direct Frequency Comb Spectroscopy of Trapped Ions Using Quantum Logic", B. Hemmerling, D. Nigg, I.V. Sherstov and P.O. Schmidt - Poster presentation
Here you can find the lists of publications of the PTB QUEST members:
QUEST Institute for Experimental Quantum Metrology
Junior Research Group "Quantum Sensors with Cold Ions"
QUEST provides regularly information about the cluster in his newsletter QUEST UPdate. The bi-annual published newsletter (in German language) is available in a printed form, as a 
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