The hope for a futuristic global quantum internet that provides robust and high-capacity quantum information transfer lies largely on qudits,the fundamental quantum information carriers prepared in high-dimensional su...The hope for a futuristic global quantum internet that provides robust and high-capacity quantum information transfer lies largely on qudits,the fundamental quantum information carriers prepared in high-dimensional superposition states.However,preparing and manipulating N-dimensional flying qudits as well as subsequently establishing their entanglement are still challenging tasks,which require precise and simultaneous maneuver of 2(N-1)parameters across multiple degrees of freedom.Here,using an integrated approach,we explore the synergy from two degrees of freedom of light,spatial mode and polarization,to generate,encode,and manipulate flying structured photons and their formed qudits in a four-dimensional Hilbert space with high quantum fidelity,intrinsically enabling enhanced noise resilience and higher quantum data rates.The four eigen spin–orbit modes of our qudits possess identical spatial–temporal characteristics in terms of intensity distribution and group velocity,thereby preserving long-haul coherence within the entirety of the quantum data transmission link.Judiciously leveraging the bi-photon entanglement,which is well preserved in the integrated manipulation process,we present versatile spin–orbit cluster states in an extensive dimensional Hilbert space.Such cluster states hold the promise for quantum error correction which can further bolster the channel robustness in long-range quantum communication.展开更多
Optical microcavities have attracted tremendous interest in both fundamental and applied research in the past few decades, thanks to their small footprint, easy integrability, and high quality factors. Using total int...Optical microcavities have attracted tremendous interest in both fundamental and applied research in the past few decades, thanks to their small footprint, easy integrability, and high quality factors. Using total internal reflection from a dielectric interface or a photonic band gap in a periodic system, these photonic structures do not rely on conventional metal-coated mirrors to confine light in small volumes, which have brought forth new developments in both classical and quantum optics. This focus issue showcases several such developments and related findings, which may pave the way for the next generation of on-chip photonic devices based on microcavities.展开更多
In this work, we first discuss systematically three general approaches to construct a non-Hermitian flat band,defined by its dispersionless real part. These approaches resort to, respectively, spontaneous restoration ...In this work, we first discuss systematically three general approaches to construct a non-Hermitian flat band,defined by its dispersionless real part. These approaches resort to, respectively, spontaneous restoration of non-Hermitian particle-hole symmetry, a persisting flat band from the underlying Hermitian system, and a compact Wannier function that is an eigenstate of the entire system. For the last approach in particular, we show the simplest lattice structure where it can be applied, and we further identify a special case of such a flat band where every point in the Brillouin zone is an exceptional point of order 3. A localized excitation in this "EP3 flat band"can display either a conserved power, quadratic power increase, or even quartic power increase, depending on whether the localized eigenstate or one of the two generalized eigenvectors is initially excited. Nevertheless, the asymptotic wave function in the long time limit is always given by the eigenstate, in this case, the compact Wannier function or its superposition in two or more unit cells.展开更多
Large-area manufacturing of flexible nanoscale electronics has long been sought by the printed electronics industry.However,the lack of a robust,reliable,high throughput and low-cost technique that is capable of deliv...Large-area manufacturing of flexible nanoscale electronics has long been sought by the printed electronics industry.However,the lack of a robust,reliable,high throughput and low-cost technique that is capable of delivering high-performance functional devices has hitherto hindered commercial exploitation.Herein we report on the extensive range of capabilities presented by adhesion lithography(a-Lith),an innovative patterning technique for the fabrication of coplanar nanogap electrodes with arbitrarily large aspect ratio.We use this technique to fabricate a plethora of nanoscale electronic devices based on symmetric and asymmetric coplanar electrodes separated by a nanogap<15 nm.We show that functional devices including self-aligned-gate transistors,radio frequency diodes and rectifying circuits,multi-colour organic light-emitting nanodiodes and multilevel non-volatile memory devices,can be fabricated in a facile manner with minimum process complexity on a range of substrates.The compatibility of the formed nanogap electrodes with a wide range of solution processable semiconductors and substrate materials renders a-Lith highly attractive for the manufacturing of large-area nanoscale opto/electronics on arbitrary size and shape substrates.展开更多
We develop a numerical scheme to construct the scattering(S) matrix for optical microcavities, including the special cases with parity-time and other non-Hermitian symmetries. This scheme incorporates the explicit for...We develop a numerical scheme to construct the scattering(S) matrix for optical microcavities, including the special cases with parity-time and other non-Hermitian symmetries. This scheme incorporates the explicit form of a nonlocal boundary condition, with the incident light represented by an inhomogeneous term. This approach resolves the artifact of a discontinuous normal derivative typically found in the R-matrix method. In addition, we show that, by excluding the aforementioned inhomogeneous term, the non-Hermitian Hamiltonian in our approach also determines the Periels–Kapur states, and it constitutes an alternative approach to derive the standard R-matrix result in this basis. Therefore, our scheme provides a convenient framework to explore the benefits of both approaches. We illustrate this boundary value problem using 1D and 2D scalar Helmholtz equations.The eigenvalues and poles of the S matrix calculated using our approach show good agreement with resultsobtained by other means.展开更多
基金National Science Foundation(NSF)(OMA-1936276,DMR-2326698,DMR-2326699)King Abdullah University of Science and Technology(OSR-2020-CRG9-4374.3)Army Research Office(W911NF2310057).
文摘The hope for a futuristic global quantum internet that provides robust and high-capacity quantum information transfer lies largely on qudits,the fundamental quantum information carriers prepared in high-dimensional superposition states.However,preparing and manipulating N-dimensional flying qudits as well as subsequently establishing their entanglement are still challenging tasks,which require precise and simultaneous maneuver of 2(N-1)parameters across multiple degrees of freedom.Here,using an integrated approach,we explore the synergy from two degrees of freedom of light,spatial mode and polarization,to generate,encode,and manipulate flying structured photons and their formed qudits in a four-dimensional Hilbert space with high quantum fidelity,intrinsically enabling enhanced noise resilience and higher quantum data rates.The four eigen spin–orbit modes of our qudits possess identical spatial–temporal characteristics in terms of intensity distribution and group velocity,thereby preserving long-haul coherence within the entirety of the quantum data transmission link.Judiciously leveraging the bi-photon entanglement,which is well preserved in the integrated manipulation process,we present versatile spin–orbit cluster states in an extensive dimensional Hilbert space.Such cluster states hold the promise for quantum error correction which can further bolster the channel robustness in long-range quantum communication.
文摘Optical microcavities have attracted tremendous interest in both fundamental and applied research in the past few decades, thanks to their small footprint, easy integrability, and high quality factors. Using total internal reflection from a dielectric interface or a photonic band gap in a periodic system, these photonic structures do not rely on conventional metal-coated mirrors to confine light in small volumes, which have brought forth new developments in both classical and quantum optics. This focus issue showcases several such developments and related findings, which may pave the way for the next generation of on-chip photonic devices based on microcavities.
基金Directorate for Mathematical and Physical Sciences(MPS)(DMR-1506987)
文摘In this work, we first discuss systematically three general approaches to construct a non-Hermitian flat band,defined by its dispersionless real part. These approaches resort to, respectively, spontaneous restoration of non-Hermitian particle-hole symmetry, a persisting flat band from the underlying Hermitian system, and a compact Wannier function that is an eigenstate of the entire system. For the last approach in particular, we show the simplest lattice structure where it can be applied, and we further identify a special case of such a flat band where every point in the Brillouin zone is an exceptional point of order 3. A localized excitation in this "EP3 flat band"can display either a conserved power, quadratic power increase, or even quartic power increase, depending on whether the localized eigenstate or one of the two generalized eigenvectors is initially excited. Nevertheless, the asymptotic wave function in the long time limit is always given by the eigenstate, in this case, the compact Wannier function or its superposition in two or more unit cells.
基金support from the European Union Horizon 2020 research and innovation programme,under the Marie Skłodowska-Curie grant agreement 706707the Engineering and Physical Sciences Research Council(EPSRC)grant no.EP/G037515/1+1 种基金the EPSRC Centre for Innovative Manufacturing in Large Area Electronics(CIM-LAE)grant no.EP/K03099X/1We also thank also Prof.Tobias Hertel for providing the PFO:(5,7)CNT material used in this work.D.D.C.B.further thanks the University of Oxford for financial support.
文摘Large-area manufacturing of flexible nanoscale electronics has long been sought by the printed electronics industry.However,the lack of a robust,reliable,high throughput and low-cost technique that is capable of delivering high-performance functional devices has hitherto hindered commercial exploitation.Herein we report on the extensive range of capabilities presented by adhesion lithography(a-Lith),an innovative patterning technique for the fabrication of coplanar nanogap electrodes with arbitrarily large aspect ratio.We use this technique to fabricate a plethora of nanoscale electronic devices based on symmetric and asymmetric coplanar electrodes separated by a nanogap<15 nm.We show that functional devices including self-aligned-gate transistors,radio frequency diodes and rectifying circuits,multi-colour organic light-emitting nanodiodes and multilevel non-volatile memory devices,can be fabricated in a facile manner with minimum process complexity on a range of substrates.The compatibility of the formed nanogap electrodes with a wide range of solution processable semiconductors and substrate materials renders a-Lith highly attractive for the manufacturing of large-area nanoscale opto/electronics on arbitrary size and shape substrates.
基金Directorate for Mathematical and Physical Sciences(MPS)(DMR-1506987)National Science Foundation(NSF)
文摘We develop a numerical scheme to construct the scattering(S) matrix for optical microcavities, including the special cases with parity-time and other non-Hermitian symmetries. This scheme incorporates the explicit form of a nonlocal boundary condition, with the incident light represented by an inhomogeneous term. This approach resolves the artifact of a discontinuous normal derivative typically found in the R-matrix method. In addition, we show that, by excluding the aforementioned inhomogeneous term, the non-Hermitian Hamiltonian in our approach also determines the Periels–Kapur states, and it constitutes an alternative approach to derive the standard R-matrix result in this basis. Therefore, our scheme provides a convenient framework to explore the benefits of both approaches. We illustrate this boundary value problem using 1D and 2D scalar Helmholtz equations.The eigenvalues and poles of the S matrix calculated using our approach show good agreement with resultsobtained by other means.
