Electrostatic potential in a superconductor

The electrostatic potential in a superconductor is studied. To this end Bardeen's extension of the Ginzburg-Landau theory to low temperatures is used to derive three Ginzburg-Landau equations - the Maxwell equation for the vector potential, the Schroedinger equation for the wave function and the Poisson equation for the electrostatic potential. The electrostatic and the thermodynamic potential compensate each other to a great extent resulting into an effective potential acting on the superconducting condensate. For the Abrikosov vortex lattice in Niobium, numerical solutions are presented and the different contributions to the electrostatic potential and the related charge distribution are discussed.Comment: 19 pages, 11 figure

Observability and Incident Response in Managed Serverless Environments Using Ontology-Based Log Monitoring

In a fully managed serverless environment, the cloud service provider is responsible for securing the cloud infrastructure, thereby reducing the operational and maintenance efforts of application developers. However, this environment limits the use of existing cybersecurity frameworks and tools, which reduces observability and situational awareness capabilities (e.g., risk assessment, incident response). In addition, existing security frameworks for serverless applications do not generalize well to all application architectures and usually require adaptation, specialized expertise, etc. for use in fully managed serverless environments. In this paper, we introduce a three-layer security scheme for applications deployed in fully managed serverless environments. The first two layers involve a unique ontology based solely on serverless logs which is used to transform them into a unified application activity knowledge graph. In the third layer, we address the need for observability and situational awareness capabilities by implementing two situational awareness tools that utilizes the graph-based representation: 1) An incident response dashboard that leverages the ontology to visualize and examine application activity logs in the context of cybersecurity alerts. Our user study showed that the dashboard enabled participants to respond more accurately and quickly to new security alerts than the baseline tool. 2) A criticality of asset (CoA) risk assessment framework that enables efficient expert-based prioritization in cybersecurity contexts