Marco Arzeo

Fast Electron Thermometry for Ultrasensitive Calorimetric Detection

We demonstrate radio-frequency thermometry on a micrometer-sized metallic island below 100 mK. Our device is based on a normal-metal-insulator-superconductor tunnel junction coupled to a resonator with transmission readout. In the first generation of the device, we achieve 90 mu K/root Hz noise-equivalent temperature with 10 MHz bandwidth. We measure the thermal relaxation time of the electron gas in the island, which we find to be of the order of 100 mu s. Such a calorimetric detector, upon optimization, can be seamlessly integrated into superconducting circuits, with immediate applications in quantum-thermodynamics experiments down to single quanta of energy.

Highly homogeneous YBCO/LSMO nanowires for photoresponse experiments

By using nanolithography and a soft etching procedure, we have realized YBa2Cu3O7-x/La0.7Sr0.3MnO3 (YBCO/LSMO) nanowires, with cross sections down to 100 x 50 nm(2) that ensure the cover age of areas up to 10 x 30 mu m(2). The LSMO layer acts as a capping for YBCO, minimizing the degradation of the superconducting properties taking place during the patterning; moreover, as a ferromagnetic manganite, it is expected to accelerate the relaxation dynamics of quasiparticles in YBCO, making such a system potentially attractive for applications in superconducting ultrafast optoelectronics. The reproducibility of the values of the critical current densities measured in different devices with the same geometry makes our nanowires ideal candidates for photoresponse experiments. First measurements have shown a satisfactory photoresponse from YBCO/LSMO devices.

Ultra low noise YBa2Cu3O7−δ nano superconducting quantum interference devices implementing nanowires

We present results on ultra low noise YBa

Microwave losses in MgO, LaAlO3, and (La0.3Sr0.7)(Al0.65Ta0.35)O3 dielectrics at low power and in the millikelvin temperature range

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Improved noise performance of ultrathin YBCO Dayem bridge nanoSQUIDs

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Toward ultra high magnetic field sensitivity YBa2Cu3O7−δ nanowire based superconducting quantum interference devices

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Microwave Losses in YBCO Coplanar Waveguide Resonators at Low Power and Millikelvin Range

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Ultra low noise YBCO nanoSQUIDs implementing nanowires

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Influence of film thickness on topology and related magnetic interactions in Fe nanoparticle films

nano Superconducting QUantum Interference Devices (nanoSQUIDs). To realize such devices, we implemented high quality YBCO nanowires, working as weak links between two electrodes. We observe critical current modulation as a function of an externally applied magnetic field in the full temperature range below the transition temperature

Ultra low noise YBa{sub 2}Cu{sub 3}O{sub 7−δ} nano superconducting quantum interference devices implementing nanowires

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