Simulations of superconducting nanostructures
Title: Simulations of superconducting nanostructures
DNr: NAISS 2023/22-1348
Project Type: NAISS Small Compute
Principal Investigator: Jack Lidmar <>
Affiliation: Kungliga Tekniska högskolan
Duration: 2023-12-15 – 2025-01-01
Classification: 10304


This project studies models of superconducting nanostructures using large scale simulations. In particular, we will study meandering nanowires, which act as superconducting single photon detectors (SSPDs). When a photon hits the wire the superconductivity is locally suppressed, which triggers a vortex to nucleate and cross the nanowire. This will in turn cause more vortices to cross and lead to a detectable voltage pulse. This complicated dynamics is poorly understood and depend on many different variables, e.g., thermal fluctuations, disorder, and geometrical details of the device. Using 2D time-dependent Ginzburg-Landau simulations we will simulate the switching current distribution of the meander, with the goal to optimize various performance measures of the detectors. At the same time, we are collaborating with experimentalists who are designing and measuring such SSPDs. A variety of different computation and simulation methods are used, e.g., finite volume solutions of stochastic time-dependent PDEs and SDEs, and Monte Carlo simulations.