2004/02/04 by Arindam Ghosh, Ghosh, Arindam, Swastik Kar +5 · 2 citations
Engineering · Physics and Astronomy · #Advanced Electrical Measurement Techniques #FOS: Physical sciences #Force Microscopy Techniques and Applications #Other Condensed Matter (cond-mat.other) #Surface and Thin Film Phenomena #cond-mat.other
paper · pdf · doi:10.48550/arxiv.cond-mat/0402130
25 pages 17 figures
arxiv created 2004/02/04 · openalex publication_date 2004/02/04 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We describe a set up for measurements of low frequency (1 mHz < f < 20 Hz) conductance fluctuations in a solid conductor. The set-up uses a five probe a.c. measurement technique and extensive digital signal processing to reach a noise floor down to Sv(f) ≤ 10-20 V2Hz-1. The set up also allows measurement of noise using an a.c. in presence of a superimposed direct current. This feature is desirable in studies of electromigration damage or in systems that show non-linear conductivity. In addition, we describe a scheme which allows us to obtain the probability density function of the conductance fluctuation after subtracting the extraneous noise contributions (background) from the observed noise. The set-up has been used for conductance fluctuation measurement in the temperature range 1.5 K < T < 500 K in the presence of magnetic fields. We present some representative data obtained by this system.