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arXiv · 1201.6289

Code-division multiplexing for x-ray microcalorimeters

G. M. Stiehl·W. B. Doriese·J. W. Fowler·G. C. Hilton·K. D. Irwin·C. D. Reintsema·D. R. Schmidt·D. S. Swetz·J. N. Ullom·L. R. Vale.
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Abstract

We demonstrate the code-division multiplexed (CDM) readout of eight transition-edge sensor microcalorimeters. The energy resolution is 3.0 eV (full width at half-maximum) or better at 5.9 keV, with a best resolution of 2.3 eV and a mean of 2.6 eV over the seven modulated detectors. The flux-summing CDM system is described and compared with similar time-division multiplexed (TDM) readout. We show that the sqrt(Npixels) multiplexing disadvantage associated with TDM is not present in CDM. This demonstration establishes CDM as both a simple route to higher performance in existing TDM microcalorimetric experiments and a long-term approach to reaching higher multiplexing factors.

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G. M. Stiehl, W. B. Doriese, J. W. Fowler, G. C. Hilton, K. D. Irwin, C. D. Reintsema, D. R. Schmidt, D. S. Swetz, J. N. Ullom, L. R. Vale.. 2012-01-30. Code-division multiplexing for x-ray microcalorimeters. https://doi.org/10.1063/1.3684807

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