Iron-Based Superconducting Nanowires: Electric Transport and Voltage-Noise Properties

Abstract

The discovery of iron-based superconductors paved the way for advanced possible applications, mostly in high magnetic fields, but also in electronics. Among superconductive devices, nanowire detectors have raised a large interest in recent years, due to their ability to detect a single photon in the visible and infrared (IR) spectral region. Although not yet optimal for single-photon detection, iron-based superconducting nanowire detectors would bring clear advantages due to their high operating temperature, also possibly profiting of other peculiar material properties. However, there are several challenges yet to be overcome, regarding mainly: fabrication of ultra-thin films, appropriate passivation techniques, optimization of nano-patterning, and high-quality electrical contacts. Test nanowire structures, made by ultra-thin films of Co-doped BaFe2As2, have been fabricated and characterized in their transport and intrinsic noise properties. The results on the realized nanostructures show good properties in terms of material resistivity and critical current. Details on the fabrication and low temperature characterization of the realized nanodevices are presented, together with a study of possible degradation phenomena induced by ageing effects.

Pressure-Induced Superconductivity in Iron-Based Spin-Ladder Compound BaFe2+δ(S1−xSex)3

“…The iron-based superconductor had a significant impact on condensed matter physics as a strongly correlated electron system based on the two-dimensional square iron lattice and exhibits characteristic magnetic phases next to the superconducting phase. These compounds triggered the extensive studies in the interplay between magnetism, orbital ordering, and superconductivity as a new material platform for further exploration of high-TC superconductors [1][2][3][4]. A stripe-type magnetic ordering is observed in the 1111, 122, 111, and 11 type iron-based superconductors [1,2,[5][6][7], and a block-type magnetic ordering is observed in 245 type iron-based superconductor [8,9].…”

Low‐Frequency Electronic Noise in Quasi‐2D van der Waals Antiferromagnetic Semiconductor FePS3—Signatures of Phase Transitions

“…electrical bias and temperature, can shed light on electron transport, carrier recombination mechanisms and, what is most important in this case, magnetic and metal-insulator phase transitions. [40][41][42][43][44][45][46] We have previously used successfully the low-frequency noise measurements as the "noise spectroscopy" for monitoring phase transitions in the 2D charge-density-wave materials; [47][48][49] examining the specifics of magnon transport in magnetic electrical insulators; [50] and clarifying the nature of electron transport in quasi-1D vdW materials. [51,52] Our measurements of noise in thin films of FePS 3 reveal a number of interesting features, which contribute to a better understanding of the properties of this AF vdW semiconductor.…”

Effect of the substrate on the electrical transport and fluctuation processes in NbRe and NbReN ultrathin films for superconducting electronics applications

“…For these reasons we have analyzed the films surfaces by atomic force microscopy (AFM) to gain additional information about the samples uniformity, roughness and crystallinity. On the other hand, the study of the charge carriers fluctuation processes provides a deeper comprehension of the physical mechanisms in a large variety of systems, as observed in iron-based superconducting materials 13 , 14 and nanowires 15 , and in granular aluminum oxide superconducting thin films 16 , 17 and nanostructures 18 , as well as in superconducting qubits 19 . Fluctuation phenomena may influence the main figures of merit of the SNSPD devices, such as jitter 20 , dark counts 21 , 22 , and latching 23 .…”