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Demonstration of code-division multiplexing for x-ray microcalorimeters



Greg Stiehl, W.Bertrand (Randy) Doriese, Gene C. Hilton, Kent D. Irwin, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Joel Ullom, Leila R. Vale, Joseph Fowler


We demonstrate the code-division multiplexing (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 multiplexing (TDM) readout. We show that the √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.
Applied Physics Letters


SQUID multiplexers, transition-edge sensors


Stiehl, G. , Doriese, W. , Hilton, G. , Irwin, K. , Reintsema, C. , Schmidt, D. , Swetz, D. , Ullom, J. , Vale, L. and Fowler, J. (2012), Demonstration of code-division multiplexing for x-ray microcalorimeters, Applied Physics Letters, [online],, (Accessed June 18, 2024)


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Created February 12, 2012, Updated October 12, 2021