TY - JOUR
T1 - Giant intrinsic circular dichroism of prolinol-derived squaraine thin films
AU - Schulz, Matthias
AU - Zablocki, Jennifer
AU - Abdullaeva, Oliya S.
AU - Brück, Stefanie
AU - Balzer, Frank
AU - Lützen, Arne
AU - Arteaga, Oriol
AU - Schiek, Manuela
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Molecular chirality and the inherently connected differential absorption of circular polarized light (CD) combined with semiconducting properties offers great potential for chiral opto-electronics. Here we discuss the temperature-controlled assembly of enantiopure prolinol functionalized squaraines with opposite handedness into intrinsically circular dichroic, molecular J-aggregates in spincasted thin films. By Mueller matrix spectroscopy we accurately probe an extraordinary high excitonic circular dichroism, which is not amplified by mesoscopic ordering effects. At maximum, CD values of 1000 mdeg/nm are reached and, after accounting for reflection losses related to the thin film nature, we obtain a film thickness independent dissymmetry factor g = 0.75. The large oscillator strength of the corresponding absorption within the deep-red spectral range translates into a negative real part of the dielectric function in the spectral vicinity of the exciton resonance. Thereby, we provide a new small molecular benchmark material for the development of organic thin film based chiroptics.
AB - Molecular chirality and the inherently connected differential absorption of circular polarized light (CD) combined with semiconducting properties offers great potential for chiral opto-electronics. Here we discuss the temperature-controlled assembly of enantiopure prolinol functionalized squaraines with opposite handedness into intrinsically circular dichroic, molecular J-aggregates in spincasted thin films. By Mueller matrix spectroscopy we accurately probe an extraordinary high excitonic circular dichroism, which is not amplified by mesoscopic ordering effects. At maximum, CD values of 1000 mdeg/nm are reached and, after accounting for reflection losses related to the thin film nature, we obtain a film thickness independent dissymmetry factor g = 0.75. The large oscillator strength of the corresponding absorption within the deep-red spectral range translates into a negative real part of the dielectric function in the spectral vicinity of the exciton resonance. Thereby, we provide a new small molecular benchmark material for the development of organic thin film based chiroptics.
U2 - 10.1038/s41467-018-04811-7
DO - 10.1038/s41467-018-04811-7
M3 - Journal article
C2 - 29925832
SN - 2041-1723
VL - 9
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 2413
ER -