Impedancemetry of multiplexed quantum devices using an on-chip cryogenic complementary metal-oxide-semiconductor active inductor

In the pursuit for scalable quantum processors,significanteffort has been devoted to the development of cryogenic classical hardware for the control and readout of a growingnumber of qubits.The current work presented a novelapproach called impedancemetry that is suitable for measuringthe quantum capacitance of semiconductor qubits connected toa resonant LC-circuit.The impedancemetry circuit exploits theintegration of a complementary metal-oxide-semiconductor(CMOS)active inductor in the resonator with tunable resonance frequency and quality factor,enabling the optimizationof readout sensitivity for quantum devices.The realized cryogenic circuit allows fast impedance detection with a measuredcapacitance resolution down to 10 aF and an input-referrednoise of 3.7 aF/Hz p.At 4.2 K,the power consumption of theactive inductor amounts to 120μW,with an additional dissipation for on-chip current excitation(0.15μW)and voltageamplification(2.9 mW)of the impedance measurement.Compared to the commonly used schemes based on dispersiveRF reflectometry which require millimeter-scale passive inductors,the circuit exhibits a notably reduced footprint(50μm360μm),facilitating its integration in a scalable quantumclassical architecture.The impedancemetry method has been applied at 4.2 K to the detection of quantum effects in the gatecapacitance of on-chip nanometric CMOS transistors that areindividually addressed via multiplexing.

Drying Drop Technology as a Possible Tool for Detection Leukemia and Tuberculosis in Cattle

Usual response of organism to viral or bacterial invasion represents antibodies production, qualitative and quantitative changes in composition of biological fluids. These changes influence conformation and surface characteristics of macromolecules (proteins), which become apparent in sessile drying drops, when they form aggregates due to salting-out effect and sediment. The bottom adsorption layers change their adhesive and viscoelastic properties in time depending on fluid composition and structure. The aim of this study was verification the idea of using this phenomenon in rapid vet diagnostics. Milk, blood and serum samples of 183 cows were tested using Drop Drying Technology (DDT). A drop of tested fluid dried on a polished quartz plate, oscillated with constant frequency—60 kHz. Mechanical properties of the drop changed during drying, influenced the electrical conductivity of the quartz plate. This signal was converted to the Acoustical- Mechanical Impedance (AMI) and displayed as a curve in coordinates AMI vs. Time. Shape of the AMI curve reflected this dynamics, and was used as a target for quantitative comparison between control and infected animals. Frequency analysis of the estimated parameters of the curves was performed using features of the Excel program. Powerful method of artificial neural network processing of the experimental data was also tested in this work as a possible tool for future development. Significant differences between control, Bovine leucosis virus positive (BLV+) and Bovine tuberculin positive (BTub+) cattle groups were obtained using all biological fluids—blood, serum and milk. We fixed also a season shift of the data, but distinction between groups still remained. In serum and milk some features of the AMI curves were more stable, and retained diagnostic properties when combined winter and spring databases. Further development of DDT is proposed.

Carbon fibres reinforced composites.Electrical impedance analysis:a gateway to smartness

For more than 7 years,our research work is focussed upon the electrical behavior of carbon fiber reinforced composites.Effectively carbon/polymeric matrix laminates can be considered as an electri-cally conductive network(i.e.carbon fibers)embedded in an insulat-ing medium(i.e.the polymeric matrix).Consequently,from an electrical point of view laminated composites have been modelled owing to combinations of electrical resistances(i.e.fibers themselves and the contact points between the fibers)and capacitances(i.e.polymeric matrix).During their manufacturing,composite material such as thermoset matrix composites for instance,undergo various changes in their physical(including electrical and mechanical)prop-erties and in their geometrical characteristics.In fact,in the case of manufacturing processes such as oven curing(vacuum bag),auto-clave curing or heating plate press,beside the chemo-rheologi-cal changes,the laminated parts are the place of a compaction phenomenon inducing changes in fiber volume fraction and thick-nesses.The idea developed in this paper is that since the carbon/polymeric matrix laminate can be considered as an electrical network,it can then be view and used as a sensor for following the material state during the manufacturing process enabling thus defects to be detected and this without any additional sensing material or device.