Welcome to the home page of the “Dynamics of Complex Quantum Systems” group at Bar-Ilan University.

We are members of the Department of Physics and of the QUEST Impact center.

First Document

Our research group is led by Emanuele Dalla Torre and studies exotic behaviors of quantum systems. We develop mathematical tools that can be used to both explain how existing quantum devices work, and to predict how new one will behave. These theoretical tools are necessary ingredients to develop devices for quantum technologies, such as quantum communication and quantum computation.

Group photo: February 2024

Recent Activities:

We study the dynamics of large and interacting systems, starting from the microscopic quantum world. Quantum mechanics follows the principle of superposition: if an atom can move to the left or to the right, it can also be in a superposition of these two states. In contrast, macroscopic objects follow the laws of classical mechanics, which do not allow any superposition. The transition from a single atom or electron to a large many-body system is pretty well understood for systems at “thermal equilibrium” at a fixed temperature. Formally, this transition involves the introduction of a forth “imaginary” direction, which accounts for the superposition of the different states. Starting from this mapping, researchers in the field many-body physics developed powerful tools to describe large quantum systems, without the need to follow each single atom.

The main goal of our group is to extend these concepts to the realm of dynamical, non-equilibrium system. Our approach to this problem is pragmatic and begins with the analysis of a specific situation, relevant to recent experiments in non-equilibrium many-body quantum systems. In some cases we try to explain measurements that were observed in the laboratory, while in others we propose new experiments and try to predict their outcome. By analyzing specific cases, we aim to establish the general rules that govern these systems, allowing us to predict their behavior with minimal effort and maximal efficiency.

In analogy to the equilibrium case, we are mostly interested in emergent collective phenomena. These properties are often universal, meaning that they do not depend on the details of the constituents. For example, equilibrium phase transitions of quantum systems in three dimensions have the same universal properties as classical systems in four dimensions (because the imaginary time plays the role of the forth dimension). Emergent phenomena of non-equilibrium systems are the focus of our research.

Click here for more details about the specific projects that we are currently involved in.