Physical properties of amorphous molybdenum silicide films for single photon detectors

Abstract

We systematically investigated the physical properties of amorphous Mo${}_{\mathrm{x}}$Si${}_{1-x}$ films deposited by the magnetron co-sputtering technique. The critical temperature $T_C$ of Mo${}_{\mathrm{x}}$ Si${}_{1-x}$ films increases gradually with the stoichiometry x, and the highest $T_C$=7.9 K was found in Mo${}_{0.83}$ Si${}_{0.17}$. Beyond $x$=0.83, preformed Cooper pairs and superconducting domains persist in the films, despite the superconducting state with perfect zero-resistivity is absent. The thick films of Mo${}_{0.83}$ Si${}_{0.17}$ show surprising degradation in which the onset of zero-resistivity is suppressed below 2 K. The thin Mo${}_{0.83}$ Si${}_{0.17}$ films, however, reveal robust superconductivity even with thickness d$\le$1 nm. We also characterized wide microwires based on the 2 nm thin Mo${}_{0.8}$ Si${}_{0.2}$ films with widths 40 and 60 $\mu$m, which show single-photon sensitivity at 780 nm and 1550 nm wavelength

References in corpus (6)

• Universal scaling of the critical temperature for thin films near the superconducting-to-insulating transition
• Characteristics of superconducting tungsten silicide WxSi1-x for single photon detection
• Different single photon response of wide and narrow superconducting MoSi strips
• Optically probing the detection mechanism in a molybdenum silicide superconducting nanowire single-photon detector
• Proximity effect model of ultra-narrow NbN strips
• Size dependent nature of the magnetic-field driven superconductor-to-insulator quantum-phase transitions

Cited by in corpus (3)

• Broadband solenoidal haloscope for terahertz axion detection
• Broadband polarization insensitivity and high detection efficiency in high-fill-factor superconducting microwire single-photon detectors
• Thin amorphous molybdenum silicide superconducting shells around individual nanowires deposited via magnetron co-sputtering