In general relativity,a gravitational“white hole”is a hypothetical region of space that cannot be entered from outside.It is the reverse of a“black hole”from which light and information cannot escape.We report an ...In general relativity,a gravitational“white hole”is a hypothetical region of space that cannot be entered from outside.It is the reverse of a“black hole”from which light and information cannot escape.We report an optical device exhibiting intriguing similarities to these objects.It will either totally absorb(optical black hole)or totally reject(optical white hole)light of any wavelength,depending on its polarization.The device’s functionality is based on the formation of a standing wave from the wavefront of spatially coherent incident radiation.Interaction of the standing wave with a thin absorber enables coherent perfect absorption and transmission,whereas polarization sensitivity arises from the geometrical phase of the interfering beams.We provide experimental proof-of-principle demonstrations and show that the device operates as a black and white hole for orthogonal polarizations of the incident light.From a remote point,it will look similar to a gravitational black or white hole depending on the polarization of light.In principle,the optical black and white hole device can operate as a deterministic absorber or rejector throughout the entire electromagnetic spectrum.Broadband absorbers and rejectors can be useful for energy harvesting,detection,stealth technologies,and redistribution of light.展开更多
基金supported by the Zepler Institute Stimulus Fund,UK’s Engineering and Physical Sciences Research Council(Grant Nos.EP/M009122/1 and EP/T02643X/1)the Singapore National Research Foundation(Grant No.NRF2021-QEP2-01-P01).
文摘In general relativity,a gravitational“white hole”is a hypothetical region of space that cannot be entered from outside.It is the reverse of a“black hole”from which light and information cannot escape.We report an optical device exhibiting intriguing similarities to these objects.It will either totally absorb(optical black hole)or totally reject(optical white hole)light of any wavelength,depending on its polarization.The device’s functionality is based on the formation of a standing wave from the wavefront of spatially coherent incident radiation.Interaction of the standing wave with a thin absorber enables coherent perfect absorption and transmission,whereas polarization sensitivity arises from the geometrical phase of the interfering beams.We provide experimental proof-of-principle demonstrations and show that the device operates as a black and white hole for orthogonal polarizations of the incident light.From a remote point,it will look similar to a gravitational black or white hole depending on the polarization of light.In principle,the optical black and white hole device can operate as a deterministic absorber or rejector throughout the entire electromagnetic spectrum.Broadband absorbers and rejectors can be useful for energy harvesting,detection,stealth technologies,and redistribution of light.
