Observation of Frenkel and charge transfer excitons in pentacene single crystals using spectroscopic generalized ellipsometry

Abstract

Observation of Frenkel and charge transfer excitons in pentacene single crystals using spectroscopic generalized ellipsometry Qi, Dongchen; Su, Haibin; Bastjan, M.; Jurchescu, O. D.; Palstra, T. M.; Wee, Andrew T. S.; Rübhausen, M.; Rusydi, A.

Consequences of Confinement Conditions on Absorption in Molecular Nanofilms

“…Comparing our research results with those obtained in [22][23][24][25], which correspond to the near UV, visible and deep IC region of electromagnetic field, one can conclude good agreement for resonant absorption, which could be attributed and explained with spatial and boundary conditions, i.e. with effect of quantum confinement and nanoscale dimensions of structures, exciton coupling and overall dynamic of excitons.…”

“…The polarizer angle which maximizes the peak at 14700 cm−1 coincides with the electric field polarization along the crystallographic b-axis, according to the ellipsometry and reflectivity calculations [23].…”

Band-to-band transitions, selection rules, effective mass, and excitonic contributions in monoclinic β−Ga2O3

“…Note that angles of incidence in element M 22 are not labeled as they are indistinguishable from each other.…”

“…Parameters of an appropriately selected physical model dielectric function (MDF) yield access to CP parameters such as band-to-band transition energies and polarization selection rules, which allow for direct comparison with results both from experiment, e.g., optical absorption and reflectance measurements, as well * Electronic mail: amock@huskers.unl.edu as from theory, e.g., density functional theory (DFT) band structure calculations [11]. A suitable and precise technique to determine the complex dielectric function tensor from arbitrarily anisotropic materials is generalized spectroscopic ellipsometry (GSE) [12][13][14][15][16][17][18][19][20][21][22][23][24]. MDF approaches were used successfully to quantify anisotropy and band-to-band transitions for many different types of materials [12,[15][16][17][18][19]21,25].…”

Characterization of molecular organization in pentacene thin films on SiO2 surface using infrared spectroscopy, spectroscopic ellipsometry, and atomic force microscopy

“…Among many organic semiconducting molecules, pentacene (PEN) is a leading molecule to have one of the highest field-effect mobility of free charge carriers and stability among organic semiconducting materials, and it is still the subject of extensive studies [8][9][10]. Thin film structures of pentacene were investigated by X-ray diffraction (XRD) [8,11], atomic force microscopy (AFM) [9,11], infrared [12][13][14][15][16] and Raman spectroscopy [11], and ellipsometry [10,[17][18][19][20] to elucidate the impact of ordering and grain morphology on OFET performance [9,21].…”