The basic indexes of all-optical integrated photonic circuits include high-density integration,ultrafast response and ultralow energy consumption.Traditional methods mainly adopt conventional micro/nano-structures.The...The basic indexes of all-optical integrated photonic circuits include high-density integration,ultrafast response and ultralow energy consumption.Traditional methods mainly adopt conventional micro/nano-structures.The overall size of the circuit is large,usually reaches hundreds of microns.Besides,it is difficult to balance the ultrafast response and ultra-low energy consumption problem,and the crosstalk between two traditional devices is difficult to overcome.Here,we propose and experimentally demonstrate an approach based on inverse design method to realize a high-density,ultrafast and ultra-low energy consumption integrated photonic circuit with two all-optical switches controlling the input states of an all-optical XOR logic gate.The feature size of the whole circuit is only 2.5μm×7μm,and that of a single device is 2μm×2μm.The distance between two adjacent devices is as small as 1.5μm,within wavelength magnitude scale.Theoretical response time of the circuit is 150 fs,and the threshold energy is within 10 fJ/bit.We have also considered the crosstalk problem.The circuit also realizes a function of identifying two-digit logic signal results.Our work provides a new idea for the design of ultrafast,ultra-low energy consumption all-optical devices and the implementation of high-density photonic integrated circuits.展开更多
Modulation of topological phase transition has been pursued by researchers in both condensed matter and optics research fields,and has been realized in Euclidean systems,such as topological photonic crystals,topologic...Modulation of topological phase transition has been pursued by researchers in both condensed matter and optics research fields,and has been realized in Euclidean systems,such as topological photonic crystals,topological metamaterials,and coupled resonator arrays.However,the spin-controlled topological phase transition in non-Euclidean space has not yet been explored.Here,we propose a non-Euclidean configuration based on Mobius rings,and we demonstrate the spin-controlled transition between the topological edge state and the bulk state.The Mobius ring,which is designed to have an 8πperiod,has a square cross section at the twist beginning and the length/width evolves adiabatically along the loop,accompanied by conversion from transverse electric to transverse magnetic modes resulting from the spin-locked effect.The 8πperiod Mobius rings are used to construct Su–Schrieffer–Heeger configuration,and the configuration can support the topological edge states excited by circularly polarized light,and meanwhile a transition from the topological edge state to the bulk state can be realized by controlling circular polarization.In addition,the spin-controlled topological phase transition in non-Euclidean space is feasible for both Hermitian and non-Hermitian cases in 2D systems.This work provides a new degree of polarization to control topological photonic states based on the spin of Mobius rings and opens a way to tune the topological phase in non-Euclidean space.展开更多
基金the National Key Research and Development Program of China under Grant No.2018YFB2200403the National Natural Science Foundation of China under Grant Nos.11734001,91950204,92150302.
文摘The basic indexes of all-optical integrated photonic circuits include high-density integration,ultrafast response and ultralow energy consumption.Traditional methods mainly adopt conventional micro/nano-structures.The overall size of the circuit is large,usually reaches hundreds of microns.Besides,it is difficult to balance the ultrafast response and ultra-low energy consumption problem,and the crosstalk between two traditional devices is difficult to overcome.Here,we propose and experimentally demonstrate an approach based on inverse design method to realize a high-density,ultrafast and ultra-low energy consumption integrated photonic circuit with two all-optical switches controlling the input states of an all-optical XOR logic gate.The feature size of the whole circuit is only 2.5μm×7μm,and that of a single device is 2μm×2μm.The distance between two adjacent devices is as small as 1.5μm,within wavelength magnitude scale.Theoretical response time of the circuit is 150 fs,and the threshold energy is within 10 fJ/bit.We have also considered the crosstalk problem.The circuit also realizes a function of identifying two-digit logic signal results.Our work provides a new idea for the design of ultrafast,ultra-low energy consumption all-optical devices and the implementation of high-density photonic integrated circuits.
基金supported by the National Natural Science Foundation of China(Grant Nos.91950204,92150302,and 12274031)the Innovation Program for Quantum Science and Technology(No.2021ZD0301502)Beijing Institute of Technology Research Fund Program for Teli Young Fellows,Beijing Institute of Technology Science and Technology Innovation Plan Innovative Talents Science,and Technology Funding Special Plan(No.2022CX01006).
文摘Modulation of topological phase transition has been pursued by researchers in both condensed matter and optics research fields,and has been realized in Euclidean systems,such as topological photonic crystals,topological metamaterials,and coupled resonator arrays.However,the spin-controlled topological phase transition in non-Euclidean space has not yet been explored.Here,we propose a non-Euclidean configuration based on Mobius rings,and we demonstrate the spin-controlled transition between the topological edge state and the bulk state.The Mobius ring,which is designed to have an 8πperiod,has a square cross section at the twist beginning and the length/width evolves adiabatically along the loop,accompanied by conversion from transverse electric to transverse magnetic modes resulting from the spin-locked effect.The 8πperiod Mobius rings are used to construct Su–Schrieffer–Heeger configuration,and the configuration can support the topological edge states excited by circularly polarized light,and meanwhile a transition from the topological edge state to the bulk state can be realized by controlling circular polarization.In addition,the spin-controlled topological phase transition in non-Euclidean space is feasible for both Hermitian and non-Hermitian cases in 2D systems.This work provides a new degree of polarization to control topological photonic states based on the spin of Mobius rings and opens a way to tune the topological phase in non-Euclidean space.
