Simone Frasca | EPFL Graph Search

Simone Frasca received his BEng in Aerospace Engineering from University of Naples "Federico II" in 2014 and his MEng in Space Engineering from University of Pisa in 2017. He undertook his Master's thesis research at the NASA Jet Propulsion Laboratory where he studied MgB2 material systems Superconducting Nanowire Single-Photon Detectors (SNSPDs). From 2017 to 2018 he was research affiliate at NASA Jet Propulsion Laboratory where he worked on ultrafast SNSPDs and their applications. Since September 2018 he has been pursuing a Ph.D. at EPFL in the Advanced Quantum Architectures Laboratory (AQUA) under the supervision of Prof. Edoardo Charbon, concentrating in fabrication of SNSPDs and focusing on possible applications like Space Imaging, LiDAR, Optical Communication and Time-Of-Flight Positron Emission Tomography (TOFPET).

High-Kinetic Inductance Superconducting Technology for Quantum Applications

Simone Frasca

Superconducting materials present unique properties, which make a potential technological platform based on superconductors extremely appealing for a wide set of applications, both classical and not. Among these classes of materials, high-kinetic inductance "dirty" superconductors, i.e. superconductors rich in impurities, offer an extra layer of flexibility in terms of achievable impedance and compactness, with applications in a variety of electronics devices and in particular in the field of sensing. By controlling and fine-tuning the superconducting properties of dirty superconductors, it is possible to design both materials and devices for optimal performance. In this dissertation, we present a platform based on different variants of niobium nitride, which are employed for distinct families of applications. First, we discuss various ways to deposit thin films of dirty superconductors, with respective advantages and disadvantages, and potential relevant design strategies. Then, we focus on four main fields of applications. The first application regards three-dimensional integration, with the use of superconducting through-silicon vias and its integration within the superconducting platform. The second is sensing, i.e. single-photon sensing and current sensing, represented respectively by superconducting nanowire single-photon detectors and nanocryotrons. Thirdly, circuits based on compact resonating structures are discussed for their applications in circuit quantum electrodynamics, first by assessing the role of kinetic inductance for internal loss and nonlinearity, and then by producing compact impedance matching structures and filters. Lastly, we present a superconducting transmon qubit based on classical superconducting materials, to be used as reference for high kinetic inductance qubits to be developed in the future.

EPFL2023

Recent advances in superconducting nanowire single-photon detector technology for exoplanet transit spectroscopy in the mid-infrared

Simone Frasca

The Origins Space Telescope mission concept includes an exoplanet transit spectrometer that requires detector arrays with ultrahigh pixel-to-pixel stability. Superconducting nanowire single-photon detectors, or SNSPDs, have the potential to meet these stringent stability requirements due to their digital-like output. Traditionally used for applications at near-IR telecom wavelengths, SNSPDs have demonstrated near-unity detection efficiencies, ultralow dark-count rates, and high dynamic ranges. Until recently, however, SNSPD operation at the mid-infrared (mid-IR) wavelengths of interest for Origins had not been demonstrated, and SNSPD formats were limited to small arrays and active areas. Recent advances in SNSPD fabrication techniques have pushed SNSPD sensitivity to wavelengths beyond 7 mu m and have enabled millimeter-scale active areas and kilopixel arrays. We report here on this progress and the outlook toward developing arrays of ultrastable superconducting nanowire single-photon detectors for mid-IR astronomy applications. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License.

SPIE-SOC PHOTO-OPTICAL INSTRUMENTATION ENGINEERS2021

System and method for removing scalloping and tapering effects in high aspect ratio through-silicon vias of wafers

Sandro Carrara, Edoardo Charbon, Simone Frasca

A method for manufacturing vias in a silicon wafer, the silicon wafer having a crystal orientation, and having a plane that is perpendicular to a surface of the wafer, tilted by 35.26°, the method comprising the steps of providing a mask having a rhomboidal-shaped opening onto a surface of the silicon wafer, such that edges of the rhomboidal-shaped opening line up with a plane of a crystalline structure of the silicon wafer, etching a hole in the silicon wafer at the rhomboidal-shaped opening, and polishing the hole after the etching by a anisotropic etching.

2021