Ultrafast Phenomena Laboratory (UPL)

Ultrafast Phenomena Laboratory (UPL)

Research topics

In the Laboratory of Ultrafast Processes, we use ultrashort laser light pulses to study phenomena occurring in matter after optical excitation.

We can track processes (e.g., structural changes, reorganization of chemical bonds) taking place in organic molecules or nanoparticles made from inorganic materials after photon absorption, or induce nonlinear phenomena, such as the simultaneous absorption of multiple photons or the frequency change of the laser light wave. Based on these capabilities, we aim to develop new photoactive materials (e.g., for emission) and to create methods for detecting pathological substances in tissues. We are also planning to begin research on the interaction of quantum states of light with matter.

The laboratory offers opportunities to conduct undergraduate, master's, and doctoral projects related to ongoing research. 

Photophysics of photoactive materials

We study the photophysical properties of new photoactive materials, such as structures that emit circularly polarized light, nanoparticles that convert infrared light into visible light, or dyes for two-photon-excited lasing, using stationary and time-resolved spectroscopic techniques. By analyzing the interaction of these materials with light and examining the influence of their environment on their photophysics, we can understand the mechanisms underlying their behavior and contribute to the optimization of the properties of new materials.

Dynamics of processes in organic molecules

The formation and breaking of chemical bonds, as well as structural changes in chemical molecules, occur in times much shorter than one picosecond. The study of such fast phenomena is only possible by using ultrashort laser light pulses lasting femtoseconds: one pulse can initiate the process under investigation, while another pulse, delayed by a set amount of time, monitors its progress. Using this scheme, we study the dynamics of elementary chemical reactions, such as hydrogen atom transfer, which allows us, among other things, to verify quantum models used to describe them.

Lasing and nonlinear optics in biological materials

Until now, light has rarely been considered in the context of diagnostic methods that could be used for imaging tissues in forms other than biopsy samples viewed under a microscope. This is due to the strong scattering of light by tissues and the low sensitivity of light to microscopic changes occurring within tissues. This situation is now changing, thanks to the development of techniques that overcome scattering and allow light to be focused deep within tissues, as well as advancements in methods based on nonlinear (multiphoton) light absorption and stimulated emission processes. By utilizing the properties of ultrashort light pulses, we are developing methods for detecting pathogenic proteins in tissues, based on, for example, the generation of laser light within the tissue under examination or stimulated emission microscopy.

Spectroscopy with quantum light

Rapidly developing quantum technologies may lead to groundbreaking inventions, such as the quantum computer, and breakthroughs in areas such as computing, telecommunications, and metrology. In recent years, there has been intensive work on developing methods for generating and modifying quantum states of light, but surprisingly little is known about the interaction of such light states with matter. We are currently working on building a source of entangled light states that can be used in spectroscopic experiments, including time-resolved measurements, where femtosecond time resolution can be achieved without the use of femtosecond laser pulse sources.