Manipulation of the electrodynamic properties of the molecular nanostructures by ultrafast twisted laser beams

The ultimate aims of studies on materials at nanoscale (<100 nm) are manufacturing of these materials, understanding and manipulation of quantum mechanical properties. Moreover, changing the structural properties of nanomaterials at atomic level and making them more functional during the synthesis will also gain advantage for new technologies. Investigation of quantum mechanical properties of nanomaterials which are industrial, cheap and easily producible is one of the primary research fields of nanotechnolgy. C_20 H_20 and benzene (C6H6) are two organic materials which are low-cost, can be produced by chemical methods and have several usage fields in industrial area. These molecules are chemically stable and have free electrons (valance electrons). Due to the free electrons, materials at nanoscale behave as a quantum well. Free electrons occupy only certain discrete energy levels, and they are promoted to higher energy levels when they obtain a convenient energy from an external source. Not only magnetic field or electric field but also electromagnetic waves can lead to excitation of electron into a higher energy level. In this study, it will be also investigated how an electromagnetic wave having a proper frequency interacts with free electrons located in molecules. Effects of electromagnetic waves, which are linearly or circularly polarized and have plane wave characteristics, on benzene and fullerene have been investigated in previous studies. In this study, effects of electromagnetic waves called as optical vortex (twisted light) which is carrying orbital momentum and, sending by ultrafast pulses, will be investigated. Here, we want to know whether angular momentum transfer of laser beams can be transfered to the free electrons inside molecule. Such a transition, will provide jumping the electrons to selected magnetic levels and obtaning a net circulation of electrons around the molecule. Circulating electron will cause a net magnetic field. When frequency, orbital momentum and number of pulse per second of light are changed, magnetic field strength and orientation will also be able to change. Change in magnetic field will also provide us to manipulate spin orientation of electron belonged to a magnetic doped which is located in suitable coordinate in molecule. In conclusion, our aim is to produce a magnetic field which can be manipulated by laser beam which is applied to nanomolecules such as benzene and fullerene and manipulating spin orientation of any electron with this magnetic field. In this regard, firstly, Gaussian 09 program and model potential method are used for calculation of molecular electronic structures. Finally, wave function of benzene is constructed using Gaussian 09 program and has been thoroughly demonstrated how it has been obtained.