On-chip characterization of low-noise microstrip-coupled transition edge sensors

Abstract

Transition edge sensors (TESs) are used extensively in millimeter-wave and submillimeter-wave astronomy. The next technological push is to reduce the noise equivalent powers from 10−17 to 10−20 W Hz−1/2 in order to take full advantage of the exceptionally low backgrounds associated with cooled-aperture space telescopes. We describe a lab-on-a-chip (LoC) for measuring the small-signal and noise properties of ultralow-noise microstrip-coupled TESs. The LoC comprises two suspended SiNx membranes, one of which supports a single-mode, variable-temperature blackbody source, and the other a microstrip-coupled TES. The two devices are connected by a superconducting microstrip transmission line. The temperature of the source is determined by Johnson noise thermometry using superconducting quantum interference device readout. In this paper, we describe the theory, layout, operation, and calibration of the experimental system and report on two prototype devices. The LoC concept has many advantages, and already we have been able to assess the optical efficiencies of our TESs. We have started to gain an appreciation of the losses associated with 100–300 GHz microminiature superconducting microstrip transmission lines at low temperatures. The next phase of our work is to apply the technique to ultralow-noise detectors, to study fluctuation phenomena in multimode devices, and to investigate the behavior of more complicated integrated circuits.

Readout-power heating and hysteretic switching between thermal quasiparticle states in kinetic inductance detectors

“…36,37 Over the temperature range 50-300 mK, structures can be produced that have thermal conductances in the range 0.1 pWK −1 to 500 pWK −1 .…”

Elastic and inelastic scattering at low temperature in low-dimensional phononic structures

“…Thus, if the temperatures of the terminations and elements are known, Eqs. (9), (17), (18), and (19) can be used to calculate the net heat flow at every plane. In fact, it is possible to calculate the correlations between any pair of the traveling-wave amplitudes.…”

“…To date, most work has considered uniform microbridges whose widths 0.5 < b < 4 μm and thicknesses 0.1 < t < 0.5 μm are either comparable with or smaller than the characteristic phonon wavelengths, and whose lengths are either much larger, l > 50 μm, [4][5][6][7][8][9] or much smaller, l < 0.5 μm, 10 than the acoustic attenuation length. In the case of very short samples, the conductance is quantum limited and is determined solely by the number of propagating modes; 11,12 in the case of very long samples, the conductance falls as some function of l due to scattering.…”

High resolution on-chip thermometry using a microstrip-coupled transition edge sensor

“…Recently we demonstrated the measurement of this broadband power using a TES. 8 The detection efficiency was very close to 100% for a short ͑Ӎ2 mm-long͒ transmission line. A variation in this approach can be used for secondary thermometry of mesoscopic devices with excellent temperature precision.…”

“…Details of our fabrication route can be found in Ref. 8. Photons transfer power between impedance-matched AuCu resistors that terminate a Nb superconducting transmission line.…”