The use of HEMTs in multiplexing large arrays of high impedance LTDs

• DOI: 10.1016/j.nima.2005.12.151
• Publication Date: 2006-01-11T14:36:36Z
• Authors: S.J.C. Yates; A. Benoit; Y. Jin; Ph. Camus; A. Cavanna; T. Durand; B. Etienne; U. Gennser; E. Grémion; C. Hoffmann; S. Leclercq; Ch. Ulysse
• Keywords: 03 medical and health sciences; 0302 clinical medicine

Abstract The use of a multiplexing system in close proximity to the detectors simplifies the electronics associated with large arrays of Low Temperature Detectors (LTDs). Here, we report the demonstration of an array of Quantum-Point-Contact High-Electron-Mobility-Transistors (QPC-HEMTs) down to 100 mK used to time multiplex the signal from 8 simulated high impedance LTDs ( ∼ 10 M Ω ) to an individual amplifier. Capacitors in parallel with the individual LTDs integrate the signal between measurements so giving a quasi-DC measurement of the LTDs. With the high impedance of the LTD this acts as a filter which counter acts the aliasing of the Johnson noise of the LTD associated with the time-multiplexing technique.