quantum metrology with atoms in a cavity

Controlling the interaction between light and matter on the level of quantum mechanics currently constitutes the state-of-the-art research in physics. For instance, a high level of control can be used to force light-matter systems to behave as other physical systems. One of the most exciting examples is the study of the so-called artificial magnetic fields exerted on neutral atoms. This can be, in principle, used to test hypotheses from distant branches of physics such as particle physics in a well-controlled and understood environment. The high level of control can be also used to create states of matter with unusual properties such as quantum entanglement. This mind-boggling phenomenon is not only of fundamental interest, but it can also find practical applications in quantum technologies. One of many examples is using entangled states to enhance the precision of measurement beyond the precision allowed by classical physics. This may lead in future the emergence of a new generation of extremely precise and compact instruments based on the foundations of quantum mechanics. The aim of the project is a theoretical description of hybrid light-matter systems from the viewpoint of precision measurements and focuses on two tasks. The first one is devoted to measurements of rotating atomic gases and resulting artificial magnetic fields by exploiting light interacting with the atoms. This may open an avenue for studying static and dynamic artificial magnetic fields from a new perspective. The second one is devoted to exploiting non- equilibrium phase transitions and exploring its metrological potential. The results of this task may lead to development of new paradigms in precision measurements.

Throughout my time as a Lise-Meitner fellow, I explored the fascinating world of quantum mechanics, focusing on the intriguing behavior of quantum systems. These systems consist of large numbers of particles that interact in complex ways, and they exhibit behaviors that defy our intuition. My research sought to uncover how these systems transition from one quantum state to another, often revealing universal principles that govern such changes. One of the highlights of my work was the study of quantum phase transitions. These are not typical transitions, like ice melting into water, but transitions that occur at the quantum level, governed by the rules of quantum mechanics. In these transitions, the system's properties change dramatically, even though there is no change in temperature. For instance, a material might suddenly become magnetic or lose its magnetic properties entirely due to changes in its internal quantum structure. By understanding these transitions, we can not only deepen our knowledge of quantum physics but also pave the way for advancements in quantum technologies, such as more precise sensors and faster quantum computers. A significant part of my research focused on the idea of "critical quantum metrology." This is a cutting-edge area where we use the sensitivity of quantum systems near a phase transition to measure physical quantities with unprecedented precision. Imagine being able to detect gravitational waves, magnetic fields, or tiny forces with accuracy far beyond what is currently possible. By harnessing the unique properties of quantum phase transitions, my work has contributed to developing new methods for ultra-precise measurements, which could have a profound impact on fields ranging from medical diagnostics to fundamental physics experiments. Another crucial aspect of my work in quantum metrology involved designing experimental proposals to enhance measurement techniques. I explored ways to amplify quantum signals and reduce noise by leveraging the unique properties of entangled quantum states. This has the potential to revolutionize technologies like atomic clocks, which are the foundation of global positioning systems, and improve the sensitivity of instruments used in scientific research and industry. These advancements could open the door to unprecedented accuracy in timekeeping, navigation, and resource exploration. In summary, my research has shed light on the universal principles of quantum phase transitions, advanced the field of quantum metrology, and proposed innovative ways to explore the frontiers of quantum mechanics. By pushing the boundaries of what we know about the quantum world, I hope this work will inspire new technologies and deepen our understanding of the universe's most fundamental laws.