We investigate the liquid-crystal (LC) alignment direction on photoalignment films formed from photosensitive polyester containing thrifluoromethyl moieties (PPDA) with various molecular weights by crossed polariz...We investigate the liquid-crystal (LC) alignment direction on photoalignment films formed from photosensitive polyester containing thrifluoromethyl moieties (PPDA) with various molecular weights by crossed polarized optical microscopy. It is found that LC alignment behaviour changes with molecular weight of PPDA. The LC alignment on PPDA irradiated films with the highest molecular weight is homogeneous, while those with low and intermediate molecular weights are homeotropic. However, surface morphologies show weak dependence on molecular weight. The surfaces are smooth and there is no clear morphological anisotropy on these aligned films observed by an atomic force microscope. The surface energies of the irradiated films are also measured by using an indirect contact-angle method where both surface energy and its polar component, increase with increasing molecular weight. Different polar surface energies can be considered as a main reason for different alignment characteristics.展开更多
We investigate the light propagation dynamics in ultra-cold Rydberg medium with inverted-Y configuration based on the superatom theory.It is viable to store light information in two types of atomic spin coherence(triv...We investigate the light propagation dynamics in ultra-cold Rydberg medium with inverted-Y configuration based on the superatom theory.It is viable to store light information in two types of atomic spin coherence(trivial spin coherence and Rydberg spin coherence),which makes the system a prospective platform for versatile light manipulation.A normal feature is to realize efficient light storage with simultaneous resonant control fields applied.An intriguing feature is to split light into two beams with different intensities and statistical properties if the control fields are applied separately.The beam of light retrieved from the Rydberg spin coherence is severely attenuated and shows anti-bunching character accompanied by the cooperative optical nonlinearity.Moreover,generation and manipulation of beating signal are achievable by applying the non-resonant control fields.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 60277033 and 50473040, and the Science Foundation of Jilin Province under Grant Nos 20020603 and 20050520.
文摘We investigate the liquid-crystal (LC) alignment direction on photoalignment films formed from photosensitive polyester containing thrifluoromethyl moieties (PPDA) with various molecular weights by crossed polarized optical microscopy. It is found that LC alignment behaviour changes with molecular weight of PPDA. The LC alignment on PPDA irradiated films with the highest molecular weight is homogeneous, while those with low and intermediate molecular weights are homeotropic. However, surface morphologies show weak dependence on molecular weight. The surfaces are smooth and there is no clear morphological anisotropy on these aligned films observed by an atomic force microscope. The surface energies of the irradiated films are also measured by using an indirect contact-angle method where both surface energy and its polar component, increase with increasing molecular weight. Different polar surface energies can be considered as a main reason for different alignment characteristics.
基金Project supported by the National Natural Science Foundation of China(Grant No.12104107)the Natural Science Foundation of Guangxi Province,China(Grant No.AD19245180)+2 种基金the Natural Science Foundation of Jilin ProvinceChina(Grant No.20220101009JC)the“Yucai Project”of Guangxi Normal University。
文摘We investigate the light propagation dynamics in ultra-cold Rydberg medium with inverted-Y configuration based on the superatom theory.It is viable to store light information in two types of atomic spin coherence(trivial spin coherence and Rydberg spin coherence),which makes the system a prospective platform for versatile light manipulation.A normal feature is to realize efficient light storage with simultaneous resonant control fields applied.An intriguing feature is to split light into two beams with different intensities and statistical properties if the control fields are applied separately.The beam of light retrieved from the Rydberg spin coherence is severely attenuated and shows anti-bunching character accompanied by the cooperative optical nonlinearity.Moreover,generation and manipulation of beating signal are achievable by applying the non-resonant control fields.