As a new concept in materials design,a variety of strategies have been developed to fabricate optical microlens arrays(MLAs)that enable the miniaturization of optical systems on the micro/nanoscale to improve their ch...As a new concept in materials design,a variety of strategies have been developed to fabricate optical microlens arrays(MLAs)that enable the miniaturization of optical systems on the micro/nanoscale to improve their characteristic performance with unique optical functionality.In this paper,we introduce a cost-effective and facile fabrication process on a large scale up to~15 inches via sequential lithographic methods to produce thin and deformable hexagonally arranged MLAs consisting of polydimethylsiloxane(PDMS).Simple employment of oxygen plasma treatment on the prestrained MLAs effectively harnessed the spontaneous formation of highly uniform nanowrinkled structures all over the surface of the elastomeric microlenses.With strain-controlled tunability,unexpected optical diffraction patterns were characterized by the interference combination effect of the microlens and deformable nanowrinkles.Consequently,the hierarchically structured MLAs presented here have the potential to produce desirable spatial arrangements,which may provide easily accessible opportunities to realize microlens-based technology by tunable focal lengths for more advanced micro-optical devices and imaging projection elements on unconventional security substrates.展开更多
We investigate the gravitational wave spectrum originating from the cosmological first-order phase transition.We compare two models:one is a scalar field model without gravitation,while the other is a scalar field mod...We investigate the gravitational wave spectrum originating from the cosmological first-order phase transition.We compare two models:one is a scalar field model without gravitation,while the other is a scalar field model with gravitation.Based on the sensitivity curves of the LISA space-based interferometer on the stochastic gravitational-wave background,we compare the difference between the gravitational wave spectra of the former and the latter cases obtained from the bubble collision process.In particular,we numerically calculate the speed of the bubble wall before collision for the two models.We demonstrate that the difference between the amplitudes of these spectra can clearly distinguish between the two models.We expect that the LISA with Signal to Noise Ratio=10 could observe the spectrum as the fast first-order phase transition.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.NRF-2021R1A5A1032937)a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI),funded by the Ministry of Health&Welfare,Republic of Korea(grant number:HI19C1085).
文摘As a new concept in materials design,a variety of strategies have been developed to fabricate optical microlens arrays(MLAs)that enable the miniaturization of optical systems on the micro/nanoscale to improve their characteristic performance with unique optical functionality.In this paper,we introduce a cost-effective and facile fabrication process on a large scale up to~15 inches via sequential lithographic methods to produce thin and deformable hexagonally arranged MLAs consisting of polydimethylsiloxane(PDMS).Simple employment of oxygen plasma treatment on the prestrained MLAs effectively harnessed the spontaneous formation of highly uniform nanowrinkled structures all over the surface of the elastomeric microlenses.With strain-controlled tunability,unexpected optical diffraction patterns were characterized by the interference combination effect of the microlens and deformable nanowrinkles.Consequently,the hierarchically structured MLAs presented here have the potential to produce desirable spatial arrangements,which may provide easily accessible opportunities to realize microlens-based technology by tunable focal lengths for more advanced micro-optical devices and imaging projection elements on unconventional security substrates.
基金BHL(2020R1F1A1075472),DY(2021R1C1C1008622,2021R1A4A5031460)WL(2016R1D1A1B01010234)were supported by the National Research Foundation of KoreaLY was supported by the Basic Science Research Program(2020R1A6A1A03047877)of the National Research Foundation of Korea funded by the Ministry of Education through Center for Quantum Spacetime(CQUeST)of Sogang University。
文摘We investigate the gravitational wave spectrum originating from the cosmological first-order phase transition.We compare two models:one is a scalar field model without gravitation,while the other is a scalar field model with gravitation.Based on the sensitivity curves of the LISA space-based interferometer on the stochastic gravitational-wave background,we compare the difference between the gravitational wave spectra of the former and the latter cases obtained from the bubble collision process.In particular,we numerically calculate the speed of the bubble wall before collision for the two models.We demonstrate that the difference between the amplitudes of these spectra can clearly distinguish between the two models.We expect that the LISA with Signal to Noise Ratio=10 could observe the spectrum as the fast first-order phase transition.