Janis Erdmanis

My name is Janis (Yanis). I have a PhD from TU Delft on the quantum effects of the superconducting phase. My passion is to seek a frame of reference to which perceived complexity becomes simple, concise and understandable, driving my lifelong learning. I enjoy building software which is robust and resilient to changing environment serving all stakeholder's needs.

I have comprehensive expertise in Julia full-stack development, encompassing a range of technologies, including HTTP, and QML, as well as the occasional utilisation of Javascript, HTML, and CSS. I possess hands-on knowledge in implementing cryptographic schemes and protocols. My involvement in the PeaceFounder project allowed me to apply concepts like public key cryptography, zero-knowledge proofs, Merkle trees, and blind signature schemes. Furthermore, I have successfully orchestrated the construction of a system from the ground up, employing both hexagonal and model-view-controller architectural paradigms. This endeavour culminated in a substantial 15,000-line codebase.

Projects I have worked on


PeaceFounder is a centralised E2E verifiable e-voting system that leverages pseudonym braiding and history trees. The immutability of the bulletin board is maintained replication-free with voter’s client devices by storing local consistency-proof chains. Meanwhile, pseudonym braiding done via an exponentiation mix before the vote allows anonymisation to be transactional with a single braider at a time. In contrast to existing E2E verifiable e-voting systems, it is much easier to deploy as the system is fully centralised, free from threshold decryption ceremonies, trusted setup phases and bulletin board replication. Furthermore, the body of votes is signed with braided pseudonyms, enabling unlimited ballot types.

This is a full-stack project with a total of 15k lines of Julia code. Following NIST specification, I have reimplemented cryptographic groups and signatures and from a research paper a Verificatum compatible verifier and prover for zero-knowledge proofs of shuffle. The server's backend exposes REST API over HTTP using JSON for communication. The client is made with QML and bridged with the client's backend.

Go to a project website Github project

My PhD thesis

In my PhD thesis, I investigated the properties of superconducting nanostructures at low temperatures and their topological characteristics in different superconducting phases. This work, a collaborative effort with my supervisor and his postdoc, resulted in four peer-reviewed publications. Additionally, I supervised a master's student. My research involved a variety of technical skills, including performing Taylor expansions, setting up Hamiltonians, diagonalizing matrices, and simulating quantum systems using Schrödinger's equation and solving stochastic differential equations. A key aspect of my work was using a PBS cluster with 200 cores for complex simulations, all conducted using the Julia programming language.

PhD Thesis

Magnetic micro-droplet in rotating field

A tiny magnetic droplet is suspended on a petri dish, and a fast-rotating magnetic field is turned on. The droplets exhibited a rich range of equilibrium shapes observed experimentally. I built a computer simulation from scratch in Julia to test the hypothesis that the equilibrium is between magnetisation force and surface tension. In the process, I came up with an innovative method for calculating the magnetic field on the droplet surface, which was critical for the project’s success. I wrapped C++ ElTopo library to refine the surface mesh adaptively. ssh and tmux were indispensable to leave my simulations running on my university's workstation for days.

Blog Paper Github

Electron on-demand emission

At a nanoscale in sub-kelvin temperatures and large magnetic fields, an electron for a few centimetres can flow coherently, just like photons on optical fibres. This enables us to envision an electron interferometer experiment on a solid-state device; thus, questions on the preparation of electron quantum state become essential. In this project, I derived and, using python, computed the resulting quantum state of an electron emitted from an electric field veil lowering one of its barriers.

Blog BSc thesis summary
CC BY-SA 4.0 Janis Erdmanis. Last modified: January 31, 2024. Website built with Franklin.jl and the Julia programming language.