In this thesis, we present experimental work on a layered material 1T-TaS$_2$. We begin by presenting a charge density wave - a state of matter with distorted
atomic lattice accompanied with the periodic modulation of conducting electron density. Then we focus on a 1T-TaS$_2$ and present its phase diagram which includes distinct charge density wave phases and a superconducting state. We describe recently discovered metastable state in 1T-TaS$_2$ that cannot be found on an equilibrium phase diagram of the material and can be excited by a laser or an electric pulse. Previous measurements and characterization of electrical switching of a 1T-TaS$_2$ is shown and picosecond electrical pulse generation by a laser excitation is presented. In experiments, optical lithography is used for microfabrication of electronic circuits for electrical measurements of 1T-TaS$_2$ crystals. Experiments on a PMMA substrate are presented, showing a significant change in a phase transition temperature between equilibrium charge density phases. We proceed by presenting a semiconductor CdMnTe, on which we fabricate a coplanar waveguide for picosecond electric pulse generation and detection with Pockels effect. To our knowledge, such experiment with picosecond electric pulse generation and detection for ultrafast phase switching of a material has not yet been reported, so it could be applied for studying fast transitions in other materials than 1T-TaS$_2$ as well. The electric pulse with an amplitude of around \SI{0.1}{\volt} and the duration of one picosecond is demonstrated. We measure electric pulse as it propagates along the waveguide and observe its spreading into a two-peak shape that we are yet to fully explain. Since the amplitude of electric pulse is too low to switch the 1T-TaS$_2$ crystal to a metastable state, we present a way to increase the pulse amplitude by improving our optical setup.
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