Lab Members

Diego is a Costa Rican physicist with research interests in quantum optics, open quantum systems, and quantum metrology. He earned his B.Sc. in Physics from the Universidad de Costa Rica in 2017 and completed his Ph.D. at Rice University in 2024. At Rice, he worked under the supervision of Dr. Han Pu, conducting research on quantum criticality in generalized versions of cornerstone quantum optics models such as the Dicke and Rabi models. 

As for his research style, Diego enjoys working on versatile projects that combine analytical modeling with numerical methods. He values close collaboration with experimental groups, while also taking interest in developing theoretical tools that support and enhance fundamental research efforts. 

He joined the Rey group as a postdoctoral researcher in September 2024, where he focuses on multi-level atoms interacting with light in cavity QED systems. His work aims to generate non-classical states for use in quantum metrology and to explore quantum simulation of complex spin models. 

In his free time, Diego enjoys playing football (soccer) and attending concerts or other music-related events. 

Matjaž finished his bachelor’s degree in physics at the University of Ljubljana. He then moved to Munich, Germany, where he completed his master’s degree at the LMU Munich. He remained in Munich to pursue his PhD in physics under the supervision of Prof. Fabian Grusdt, focusing on confined phases in lattice gauge theories coupled to matter. 

His broad research interests are strongly correlated many-body systems and quantum simulation of such systems. He likes to solve physics problems using numerical simulations employing matrix-product states and developing effective theories of complex problems. 

He joined the Rey group in the fall of 2024 as a postdoc. His main research focus at JILA is the theoretical study of the dynamics of doped, strongly interacting many-body systems, which can be simulated in optical experiments.  

In his free time, he enjoys hiking and climbing. 

David Wellnitz is broadly interested in the interface of atomic and molecular physics with quantum technologies, and the numerical simulation of quantum many-body systems. Following his undergraduate and masters studies at Heidelberg University in Germany, he moved to the University of Strasbourg in France to pursue a PhD in physics in the group of Johannes Schachenmayer and Guido Pupillo in 2018. In his PhD, he developed numerical methods to study quantum many-body dynamics and applied them to investigate how the interaction of molecules with light confined in optical cavities modify their chemical reactions. He joined the Rey group in March 2022 as a postdoctoral researcher. Here, he studies quantum many-body dynamics of molecules at temperatures near absolute zero for quantum simulation. 

Outside of physics, he enjoys a good game of chess and likes to go hiking. 

He earned his BSc in Physics from the Universidad Nacional de Colombia in 2018. He began his PhD in Physics at the University of Colorado Boulder in Fall 2020 and joined Prof. Rey’s research group at JILA in Summer 2021, collaborating with experimental groups to integrate theoretical models into ongoing experiments. His interests center on computational and numerical modeling of many-body quantum systems. He is currently focused on leveraging dissipative processes and symmetry-protected protocols to generate and optimize spin squeezing by engineering dissipation-induced superradiant transitions in cavity QED; and implementing phonon-mediated schemes for quantum-information tasks such as quantum teleportation of collective spin states using ion traps as platform. He is also exploring black-hole–inspired algorithms on trapped-ion for applications of information scrambling. 

Jaeyong (goes by Jay) graduated from Korea Advanced Institute of Science and Technology (KAIST) with BS degree in physics major in 2023. During his undergraduate program, he worked on theoretical study of combinatorial optimization problem solving with Rydberg atom array using adiabatic passage, QAOA, etc. After joining the group at the end of 2023, he focuses on the study of controlling motional state of neutral atoms trapped in optical tweezers by parametrically modulating the potential.  

He earned his B.Sc. in physics from Huazhong University of Science and Technology in 2021. He then pursued graduate studies at Sun Yat-sen University, receiving his M.Sc. in 2024. During his master’s program, he worked on controlling topological edge states with waveguide QED and developed the theory for chiral dynamics in coupled quantum systems. 

With a strong interest in the interplay between light–matter interactions and many-body physics, he decided to engage in ultracold-atom research. He began his Ph.D. at the University of Colorado Boulder and joined Rey’s group at the end of his first year in 2025. He currently investigates collective spin dynamics and quantum simulations in cavity QED systems.