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In physics and physical chemistry, time-resolved spectroscopy is the study of dynamic processes in materials or chemical compounds by means of spectroscopic techniques.Most often, processes are studied after the illumination of a material occurs, but in principle, the technique can be applied to any process that leads to a change in properties of a material.
Time-resolved two-photon photoelectron (2PPE) spectroscopy is a time-resolved spectroscopy technique which is used to study electronic structure and electronic excitations at surfaces. [ 1 ] [ 2 ] The technique utilizes femtosecond to picosecond laser pulses in order to first photoexcite an electron.
Principle of angle-resolved photoemission spectroscopy.. Photoemission spectroscopy (PES), also known as photoelectron spectroscopy, [1] refers to energy measurement of electrons emitted from solids, gases or liquids by the photoelectric effect, in order to determine the binding energies of electrons in the substance.
Angle-resolved photoemission spectroscopy (ARPES) is an experimental technique used in condensed matter physics to probe the allowed energies and momenta of the electrons in a material, usually a crystalline solid. It is based on the photoelectric effect, in which an incoming photon of sufficient energy ejects an electron from the surface of a ...
Femtosecond laser-based ARPES can be extended to give spectroscopic access to excited states in time-resolved photoemission and two-photon photoelectron spectroscopy. By pumping an electron to a higher level excited state with the first photon, the subsequent evolution and interactions of electronic states as a function of time can be studied ...
The resolution of PEEM is limited to about 10 nm, which results from a spread of the photoelectron emission angle. Angle resolved photoemission spectroscopy is a powerful tool for structure analysis. However, it may be difficult to make angle-resolved and energy-selective PEEM measurements because of a lack of intensity.
Ultrafast laser spectroscopy is a category of spectroscopic techniques using ultrashort pulse lasers for the study of dynamics on extremely short time scales (attoseconds to nanoseconds). Different methods are used to examine the dynamics of charge carriers, atoms, and molecules.
Photoelectron photoion coincidence spectroscopy (PEPICO) is a combination of photoionization mass spectrometry and photoelectron spectroscopy. [1] It is largely based on the photoelectric effect . Free molecules from a gas-phase sample are ionized by incident vacuum ultraviolet (VUV) radiation.