We investigate theoretically single photon transport properties in coupled-resonator waveguide coupling with a nanocavity interacting with an external mirror. By using the discrete coordinates approach, transmission a...We investigate theoretically single photon transport properties in coupled-resonator waveguide coupling with a nanocavity interacting with an external mirror. By using the discrete coordinates approach, transmission and reflection amplitudes of the propagating single photon in the waveguide are obtained. The influence of the coupling strength between the nanocavity and the external mirror on the single photon scattering spectra is discussed. We also extend the results to the waveguide with linear and quadratic form dispersion relations.展开更多
The photon transport properties in one-dimensional coupled-resonator waveguide embedded with a quantum dot molecule are investigated. The calculations reveal that one can control the photon transport by using a gate e...The photon transport properties in one-dimensional coupled-resonator waveguide embedded with a quantum dot molecule are investigated. The calculations reveal that one can control the photon transport by using a gate electric field. The phase shift and group velocity delay of the transmitted single photon are discussed. This research may be found applications in integrated optoelectronic devices and solid quantum devices.展开更多
We discuss a new class of high-Q nonlocal metasurfaces composed of weakly coupled optical waveguides with a periodically broken translational symmetry.The physics of such metasurfaces can be understood with the concep...We discuss a new class of high-Q nonlocal metasurfaces composed of weakly coupled optical waveguides with a periodically broken translational symmetry.The physics of such metasurfaces can be understood with the concept of coupled-resonator optical waveguides(CROWs)developed earlier for in-plane propagation of light in arrays of optical microresonators and photonic crystal cavities,allowing us to realize photonic flatbands that exhibit uniform response to the resonant light across a wide range of incident angles.We suggest several realizations of this concept for anisotropic metasurfaces and demonstrate experimentally how such CROW-inspired metasurfaces can be employed to achieve unidirectional and bidirectional linear polarization flatbands,as well as chiral flatbands that are highly selective to the circular polarization of the incoming light.展开更多
A coupled resonator diplexer has been designed, fabricated, and tested. The design is based on synthesis of coupling matrix of a 3-port coupled resonator circuit using optimization. Unlike conventional diplexers, the ...A coupled resonator diplexer has been designed, fabricated, and tested. The design is based on synthesis of coupling matrix of a 3-port coupled resonator circuit using optimization. Unlike conventional diplexers, the presented diplexer configuration does not include any separate junctions for distribution of energy. The diplexer has been implemented at X-band with waveguide cavity resonators, and its measured response is in good agreement with the simulated response.展开更多
We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two ty...We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two typical bound states found above and below the energy bands,this system presents an extraordinary chiral bound state located within the energy gap.We use the chirality to quantify the breaking of the mirror symmetry.We find that the chirality value undergoes continuous changes by tuning the coupling strengths.The preferred direction of the chirality is controlled not only by the competition between the intracell and the intercell hoppings in the coupled-resonator array,but also by the coherence between the two coupling points.In the case with one coupling point,the chirality values varies monotonously with difference between the intracell hopping and the intercell hoppings.While in the case with two coupling points,due to the coherence between the two coupling points the perfect chiral states can be obtained.展开更多
We study the single-photon transport in the coupled-resonator waveguide(CRW)controlled by an imperfect cavity.A Lorentzian spectrum is introduced to describe the dissipation.We find that the probability current conser...We study the single-photon transport in the coupled-resonator waveguide(CRW)controlled by an imperfect cavity.A Lorentzian spectrum is introduced to describe the dissipation.We find that the probability current conservation can be broken,although the imperfect cavity is a Hermitian system.The coupling strength between the imperfect cavity and the CRW has significant influences near the resonant frequency.With the increase of the coupling strength,the transmission coeffi-cient becomes smaller.The spectral width plays a dominant role under the off-resonant condition,where the transmission coefficient is greatly suppressed with the increase of the spectral width.We also observe an abrupt jump of the transmission and reflection coefficients when the hopping amplitude is large enough.All the distinctive behaviors are closely related to the complex effective potential induced by the imperfect cavity.展开更多
The light transmission properties through two-dimensional photonic crystal waveguides based on coupling of square cavities are studied by the finite-difference time-domain technique.Through interlacing the adjacent ca...The light transmission properties through two-dimensional photonic crystal waveguides based on coupling of square cavities are studied by the finite-difference time-domain technique.Through interlacing the adjacent cavities along the direction vertical to the waveguide,the coupling distance between the adjacent cavities is extended,and the group velocity of the guiding modes can be slowed by five-fold compared with that in vacuum.Because of the different spatial field distributions of various resonant modes,the corresponding group velocities are also different for the same CROW structure.展开更多
Slow light with high group index and wideband is achieved in photonic crystal coupled-resonator optical waveguides （PC-CROWs）. According to the eye-shaped scatterers and various microcavities, saddle- like curves be...Slow light with high group index and wideband is achieved in photonic crystal coupled-resonator optical waveguides （PC-CROWs）. According to the eye-shaped scatterers and various microcavities, saddle- like curves between the normalized frequency f and wave number k can be obtained by adjusting the parameters of the scatterers, parameters of the coupling microcavities, and positions of the scatterers. Slow light with decent flat band and group index can then be achieved by optimizing the parameters. Simulations prove that the maximal value of the group index is 〉 104, and the normalized delay bandwidth product within a new varying range of ng 〉 102 or ng 〉 103 can be a new and effective criterion of evaluation for the slow light in PC-CROWs.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.11105001 and 61472282the Anhui Provincial Natural Science Foundation under Grant Nos.1408085QA22,1608085MA09,and 1508085MF129
文摘We investigate theoretically single photon transport properties in coupled-resonator waveguide coupling with a nanocavity interacting with an external mirror. By using the discrete coordinates approach, transmission and reflection amplitudes of the propagating single photon in the waveguide are obtained. The influence of the coupling strength between the nanocavity and the external mirror on the single photon scattering spectra is discussed. We also extend the results to the waveguide with linear and quadratic form dispersion relations.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 11004001 and 11105001the Key Project of Chinese Ministry of Education under Grant No. 212076the Anhui Provincial Natural Science Foundation under Grant No. 1208085QA09
文摘The photon transport properties in one-dimensional coupled-resonator waveguide embedded with a quantum dot molecule are investigated. The calculations reveal that one can control the photon transport by using a gate electric field. The phase shift and group velocity delay of the transmitted single photon are discussed. This research may be found applications in integrated optoelectronic devices and solid quantum devices.
基金supported by the National Natural Science Foundation of China(Grant No.12274269)the National Key Research and Development Program of China(Grant No.2022YFA1404800)+1 种基金the Australian Research Council(Grant No.DP210101292)the International Technology Center Indo-Pacific(ITC IPAC)via Army Research Office(Contract No.FA520923C0023).
文摘We discuss a new class of high-Q nonlocal metasurfaces composed of weakly coupled optical waveguides with a periodically broken translational symmetry.The physics of such metasurfaces can be understood with the concept of coupled-resonator optical waveguides(CROWs)developed earlier for in-plane propagation of light in arrays of optical microresonators and photonic crystal cavities,allowing us to realize photonic flatbands that exhibit uniform response to the resonant light across a wide range of incident angles.We suggest several realizations of this concept for anisotropic metasurfaces and demonstrate experimentally how such CROW-inspired metasurfaces can be employed to achieve unidirectional and bidirectional linear polarization flatbands,as well as chiral flatbands that are highly selective to the circular polarization of the incoming light.
文摘A coupled resonator diplexer has been designed, fabricated, and tested. The design is based on synthesis of coupling matrix of a 3-port coupled resonator circuit using optimization. Unlike conventional diplexers, the presented diplexer configuration does not include any separate junctions for distribution of energy. The diplexer has been implemented at X-band with waveguide cavity resonators, and its measured response is in good agreement with the simulated response.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11975095,12075082,11935006,and 12247105)the Major Sci-Tech Program of Hunan Province,China(Grant No.2023ZJ1010)the Natural Science Foundation of Guangdong Province,China(Grant Nos.2019A1515011400 and 2023A151501223).
文摘We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two typical bound states found above and below the energy bands,this system presents an extraordinary chiral bound state located within the energy gap.We use the chirality to quantify the breaking of the mirror symmetry.We find that the chirality value undergoes continuous changes by tuning the coupling strengths.The preferred direction of the chirality is controlled not only by the competition between the intracell and the intercell hoppings in the coupled-resonator array,but also by the coherence between the two coupling points.In the case with one coupling point,the chirality values varies monotonously with difference between the intracell hopping and the intercell hoppings.While in the case with two coupling points,due to the coherence between the two coupling points the perfect chiral states can be obtained.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11834005 and 11674285)。
文摘We study the single-photon transport in the coupled-resonator waveguide(CRW)controlled by an imperfect cavity.A Lorentzian spectrum is introduced to describe the dissipation.We find that the probability current conservation can be broken,although the imperfect cavity is a Hermitian system.The coupling strength between the imperfect cavity and the CRW has significant influences near the resonant frequency.With the increase of the coupling strength,the transmission coeffi-cient becomes smaller.The spectral width plays a dominant role under the off-resonant condition,where the transmission coefficient is greatly suppressed with the increase of the spectral width.We also observe an abrupt jump of the transmission and reflection coefficients when the hopping amplitude is large enough.All the distinctive behaviors are closely related to the complex effective potential induced by the imperfect cavity.
基金supported by the National Natural Science Foundation of China(Grant Nos.10904176 and 11004169)the Fundamental Research Funds for the Central Universities+1 种基金the "985 Project"(Grant No.985-07012009)the "211 Project" of the Ministry of Education of China
文摘The light transmission properties through two-dimensional photonic crystal waveguides based on coupling of square cavities are studied by the finite-difference time-domain technique.Through interlacing the adjacent cavities along the direction vertical to the waveguide,the coupling distance between the adjacent cavities is extended,and the group velocity of the guiding modes can be slowed by five-fold compared with that in vacuum.Because of the different spatial field distributions of various resonant modes,the corresponding group velocities are also different for the same CROW structure.
基金This work was supported by the National Natural Science Foundation of China （Grant No. 11144007） and the Natural Science Foundation of Shandong Province （Grant No. ZR2016AM27）.
文摘Slow light with high group index and wideband is achieved in photonic crystal coupled-resonator optical waveguides （PC-CROWs）. According to the eye-shaped scatterers and various microcavities, saddle- like curves between the normalized frequency f and wave number k can be obtained by adjusting the parameters of the scatterers, parameters of the coupling microcavities, and positions of the scatterers. Slow light with decent flat band and group index can then be achieved by optimizing the parameters. Simulations prove that the maximal value of the group index is 〉 104, and the normalized delay bandwidth product within a new varying range of ng 〉 102 or ng 〉 103 can be a new and effective criterion of evaluation for the slow light in PC-CROWs.
