With this project, you will join a team of experimental and theoretical quantum physicists at the University of Amsterdam under the supervision of Arghavan Safavi-Naini. Our theory team is active both on proposing next generation protocols and devices for quantum computation and quantum information theory, as well as closely collaborating with the groups of Rene Gerritsma and Florian Schreck to guide and support the current generation of experiments.

Quantum many-body systems with spin and motional degrees of freedom play an important role in quantum simulation and quantum computation. They underlie many of the leading quantum simulation platforms ranging from superconducting circuits to trapped ions, and form the underlying Hamiltonians of paradigmatic problems in impurity physics, quantum chemistry, and polaritonic chemistry, where their study promises to predict quantum many-body dynamics of molecules and control chemical reactions.

Thus, the ability to understand steady-state properties, as well as the dynamics of spin-boson systems (both closed and in the presence of an environment) is crucial to advancing current NISQ platforms, developing protocols for robust state preparation, and extending the level of control over the aforementioned polaritonic chemistry. However, the complex nature of the Hamiltonians and infinite-dimensional bosonic Hilbert space means that so far, no single treatment has been able to tackle the range of systems described by spin-boson type Hamiltonians or even the full parameter space of a specific model.

In the past three years our group has developed a new approach based on non-Gaussian variational ansatz applicable to a broad class of spin-boson Hamiltonians in both open and closed systems. However, so far, our approach has been limited to ~3-5 spins coupled to several bosonic modes (see publications of Liam Bond on hqys.nl). In this project we will recast our method in the matrix product state (MPS) language. We will use the formalism developed for Gaussian states to construct a non-Gaussian ansatz for the bosons, with an additional local spin degree of freedom. This will enable to model a variety of spin-boson Hamiltonians, with typical sources of dissipation, with application to quantum simulation and polaritonic chemistry. 

• at least 8 months of master project in either condensed matter theory, quantum optics, or quantum computing and simulation.
• good team working skills;
• good English skills;
• programming skills;
• strong letter of recommendation from master project supervisor;
• Beneficial skill: familiarity with a numerical method such as matrix product states, knowledge of open quantum systems, strong mathematics background

For MSCA PhD positions it is required that the applicant shall at the date of recruitment be in the first four years (full-time equivalent research experience) of their research careers and have not been awarded a doctoral degree. The applicant must not have resided or carried out her/his main activity (e.g. work or studies) in the Netherlands for more than 12 months in the three years immediately prior the recruitment date.

A temporary contract for 38 hours per week for the duration of 4 years (the initial contract will be for a period of 18 months and after satisfactory evaluation it will be extended for a total duration of 4 years). The preferred starting date is 1 October 2025 or as soon as possible after that. This should lead to a dissertation (PhD thesis). We will draft an educational plan that includes attendance of courses and (international) meetings. We also expect you to assist in teaching undergraduates and master students.