Information Processing Chips Research Articles

Fano Resonance Properties in (K3C6o / HgBa2Ca2Cu3O10) 1D photonic crystal

The Fano resonance and Electromagnetic induced reflectance (EIR) properties in one-dimensional superconductor photonic crystals (SPCs) have been investigated theoretically by Transfer Matrix Method (TMM). The periodic structure consists of alternating of pair superconductor materials are made of (K3C60/HgBa2Ca2Cu3O10) one-dimensional photonic crystal. The SPCs is enclosed by dielectric cap layer at different induced fields. To exam the efficiency of the reported structure, different parameters are used for analysis such as layers thicknesses, temperature, angle of incidence and the dielectric constant, dielectric cap layer on the EIR and Fano line shape. The investigation results exhibits tunable Fano resonances and EIR resonance peaks accompanied by asymmetrical line shape very sensitive to dielectric cap layer, constituent materials and dependence incidence angle. This will be useful reference for different applications of photonic topological states in the integrated photonic devices and information processing chips.

Ultracompact and Unidirectional On-Chip Light Source Based on Epsilon-Near-Zero Materials in an Optical Communication Range

On-chip light sources are essential components for integrated photonic circuits and quantum information processing chips. High directionality, high collection efficiency, and ultrasmall feature size are the most significant features for a light source in the wavelength range for optical communication, around 1550 nm. The authors use nanomanipulation to create an ultrasmall, unidirectional on-chip light source based on PbS quantum dots and an epsilon-near-zero (ENZ) material. This work not only shows the way to integrated photonic devices based on ENZ materials, but also provides an advanced method for the precise assembly of composite functional nanostructures.

Advanced technologies for quantum photonic devices based on epitaxial quantum dots.

Quantum photonic devices are candidates for realizing practical quantum computers and networks. The development of integrated quantum photonic devices can greatly benefit from the ability to incorporate different types of materials with complementary, superior optical or electrical properties on a single chip. Semiconductor quantum dots (QDs) serve as a core element in the emerging modern photonic quantum technologies by allowing on-demand generation of single-photons and entangled photon pairs. During each excitation cycle, there is one and only one emitted photon or photon pair. QD photonic devices are on the verge of unfolding for advanced quantum technology applications. In this review, we focus on the latest significant progress of QD photonic devices. We first discuss advanced technologies in QD growth, with special attention to droplet epitaxy and site-controlled QDs. Then we overview the wavelength engineering of QDs via strain tuning and quantum frequency conversion techniques. We extend our discussion to advanced optical excitation techniques recently developed for achieving the desired emission properties of QDs. Finally, the advances in heterogeneous integration of active quantum light-emitting devices and passive integrated photonic circuits are reviewed, in the context of realizing scalable quantum information processing chips.

Superconducting Coplanar Waveguide Resonators Capable of Cofabrication with Josephson Junctions

Superconducting coplanar waveguide resonators and Josephson junctions are crucial components of superconducting quantum information processing chips. Resonators are usually fabricated through lift-off or etching, while Josephson junctions are made by trilayer process or double-angle evaporation. To simplify the fabrication process, we propose a scheme that uses the same process steps for both Josephson junctions and resonators. Simulations and experiments are conducted to confirm that resonators fabricated via the proposed process have quality factor comparable to those via traditional process. This work paves the way for quantum information processing on superconducting large-scale integrated circuits.

On‐Chip Dual Electro‐Optic and Optoelectric Modulation Based on ZnO Nanowire‐Coated Photonic Crystal Nanocavity

AbstractElectronic–photonic hybrid integrated circuits represent the essential basis of next‐generation ultrahigh‐speed information processing chips, which will require ultrafast and ultralow‐energy‐consumption electronic and photonic information interconversion and modulation, i.e., on‐chip dual electro‐optic and optoelectric modulation. However, this type of modulation has not been realized to date because of an absence of materials that demonstrate sufficient intrinsic electro‐optic and optoelectric responses simultaneously. On‐chip dual electro‐optic and optoelectric modulation is experimentally realized here based on refractive index variation of a ZnO nanowire driven by the gate voltage and electrical conductivity changes in this nanowire caused by the strong localized light field of a silicon nitride photonic crystal nanocavity mode. A low gate voltage of 1.5 V induces a large shift of 7 nm in the Fano‐like resonance wavelength and modulates the propagation state of an 800 nm light signal with a large modulation depth of 75%. Additionally, weak signal light with power as low as 0.4 µW induces a modulation depth of 60% in the electric signal. On‐chip conversion between electronic and photonic signals thus is achieved. This work paves the way toward realization of novel nanoscale multifunctional optoelectronic integrated devices and provides an on‐chip platform for the study of new optoelectronic functional materials.

Fano-resonance in one-dimensional topological photonic crystal heterostructure.

We theoretically realize the Fano resonance with a high quality factor of 106 using a structure, which is constructed from three one-dimensional photonic crystals and a defect layer. The emerged Fano resonance can be attributed to the weak coupling between a Fabry-Perot cavity mode and a topological edge state mode provided by the topological photonic crystal heterostructure. Moreover, we experimentally reproduce this Fano resonance in the optical communication range with a high quality of 104. This may be useful reference for the study of applications of photonic topological states in integrated photonic devices and information processing chips.

Low-power, ultrafast, and dynamic all-optical tunable plasmon induced transparency in two stub resonators side-coupled with a plasmonic waveguide system

We theoretically and numerically investigate a low-power, ultrafast, and dynamic all-optical tunable plasmon induced transparency (PIT) in two stub resonators side-coupled with a metal-dielectric-metal (MDM) plasmonic waveguide system. The optical Kerr effect is enhanced by the local electromagnetic field of surface plasmon polaritons (SPPs) and the plasmonic waveguide based on graphene-Ag composite material structures with large effective Kerr nonlinear coefficient. An ultrafast response time of the order of 1 ps is reached because of ultrafast carrier relaxation dynamics of graphene. With dynamically tuning the propagation phase of the plasmonic waveguide, π-phase shift of the transmission spectrum in the PIT system is achieved under excitation of a pump light with an intensity as low as 5.8 MW cm−2. The group delay is controlled between 0.14 and 0.67 ps. Moreover, the tunable bandwidth of about 42 nm is obtained. For the indirect coupling between two stub cavities or the phase coupling scheme, the phase shift multiplication effect of the PIT effect is found. All observed schemes are analyzed rigorously through finite-difference time-domain simulations and coupled-mode formalism. This work not only paves the way towards the realization of on-chip integrated nanophotonic devices but also opens the possibility of the construction of ultrahigh-speed information processing chips based on plasmonic circuits.

All-optical tunable dual Fano resonance in nonlinear metamaterials in optical communication range

Low-power, ultra-fast all-optical tunable dual Fano resonance was realized in a metamaterial coated with a non-linear nanocomposite layer composed of gold nanoparticle-doped polycrystalline barium strontium titanate and multilayer tungsten disulphide microsheets. A high non-linear refractive index of −2.148 × 10−11 m2/W was achieved in the nanocomposite material that originated in the non-linearity enhancement associated with the quantum confinement effect, the local-field enhancement effect, and reinforced interactions between photons and the multilayer tungsten disulphide microsheets. An ultra-low threshold pump intensity of 600 kW/cm2 was obtained. An ultra-fast response time of 25.4 ps was maintained because of the fast relaxation dynamics of the bound electrons in the nanoscale polycrystalline barium strontium titanate grains. The large third-order non-linear responses of the metamaterial were confirmed with a high third harmonic generation conversion efficiency of 5.4 × 10−5. This work may help to pave the way towards realization of ultra-high-speed information processing chips and multifunctional integrated photonic devices based on metamaterials.

Ultrafast on‐Chip Remotely‐Triggered All‐Optical Switching Based on Epsilon‐Near‐Zero Nanocomposites

On-chip-triggered all-optical switching is a key component of ultrahigh-speed and ultrawide-band information processing chips.[1-4] This switching technique, the operating states of which are triggered by a remote control light, paves the way for the realization of cascaded and complicated logic processing circuits and quantum solid chips. Here, a strategy is reported to realize on-chip remotely-triggered, ultralow-power, ultrafast, and nanoscale all-optical switching with high switching efficiency in integrated photonic circuits. It is based on control-light induced dynamic modulation of the coupling properties of two remotely-coupled silicon photonic crystal nanocavities, and extremely large optical nonlinearity enhancement associated with epsilon-near-zero multi-component nanocomposite achieved through dispersion engineering. Compared with previous reports of on-chip direct-triggered all-optical switching, the threshold control intensity, 560 kW/cm2, is reduced by four orders of magnitude, while maintaining ultrafast switching time of 15 ps. This not only provides a strategy to construct photonic materials with ultrafast and large third-order nonlinearity, but also offers an on-chip platform for the fundamental study of nonlinear optics.

Light‐switching‐light optical transistor based on metallic nanoparticle cross‐chains geometry incorporating Kerr nonlinearity

In this research work, we propose all‐optical transistor based on metallic nanoparticle cross‐chains geometry. The geometry of the proposed device consists of two silver nanoparticle chains arranged along the x‐ and z‐axis. The x‐chain contains a Kerr nonlinearity, the source beam is set at the left side of the later, while the control beam is located at the top side of the z‐chain. The control beam can turn ON and OFF the light transmission of an incoming light. We report a theoretical model of a very small all‐optical transistor proof‐of‐conceptmade of optical ‘light switching light'concept. We show that the transmission efficiency strongly depends on the control beam and polarization of the incoming light. We investigate the influence of a perfect reflector and reflecting substrate on the transmission of the optical signal when the control beam is turned ON and OFF. These new findings make our unique design a potential candidate for future highly‐integrated optical information processing chips.

Nanoscale on-chip all-optical logic parity checker in integrated plasmonic circuits in optical communication range.

The nanoscale chip-integrated all-optical logic parity checker is an essential core component for optical computing systems and ultrahigh-speed ultrawide-band information processing chips. Unfortunately, little experimental progress has been made in development of these devices to date because of material bottleneck limitations and a lack of effective realization mechanisms. Here, we report a simple and efficient strategy for direct realization of nanoscale chip-integrated all-optical logic parity checkers in integrated plasmonic circuits in the optical communication range. The proposed parity checker consists of two-level cascaded exclusive-OR (XOR) logic gates that are realized based on the linear interference of surface plasmon polaritons propagating in the plasmonic waveguides. The parity of the number of logic 1s in the incident four-bit logic signals is determined, and the output signal is given the logic state 0 for even parity (and 1 for odd parity). Compared with previous reports, the overall device feature size is reduced by more than two orders of magnitude, while ultralow energy consumption is maintained. This work raises the possibility of realization of large-scale integrated information processing chips based on integrated plasmonic circuits, and also provides a way to overcome the intrinsic limitations of serious surface plasmon polariton losses for on-chip integration applications.

Multilayer-MoS2-microsheet/(Nano-Au:LiNbO3) for all-optical tunable metamaterial-induced transparency

All-optical tunable metamaterial-induced transparency is realized using polycrystalline lithium niobate doped with gold nanoparticles and multilayer molybdenum disulfide microsheets as a third-order nonlinear optical material. A low threshold pump intensity of 90 kW cm−2 is obtained based on nonlinearity enhancement associated with the quantum confinement effect, the local-field enhancement effect, and reinforced interaction between photons and the multilayer molybdenum disulfide microsheets. An ultrafast response time of 27.4 ps is maintained owing to the fast relaxation dynamics of bound electrons in the polycrystalline lithium niobate. This work may pave a way for the realization of ultrahigh speed information processing chips based on metamaterials.

Low-power and ultrafast all-optical tunable plasmon induced transparency in metal-dielectric-metal waveguide side-coupled Fabry-Perot resonators system

In this paper, low-power and ultrafast all-optical tunable plasmon induced transparency in metal-dielectric-metal (MDM) waveguide side-coupled Fabry-Perot (FP) resonators system with nonlinear optical Kerr medium is investigated both analytically and numerically. High tunability in transparency window magnitude and phase responses is obtained when nonlinear optical Kerr material is embedded in the MDM waveguide. In order to reduce the pump intensity, traditional nonlinear optical Kerr material is replaced by graphene. A shift of 64 nm in the central wavelength of the transparency window is achieved when the FP resonators are covered with monolayer graphene with pump intensity increasing from 9.2 to 10 MW/cm2. An ultrafast response time of the order of 1 ps is reached because of ultrafast carrier relaxation dynamics of graphene. This work not only paves the way towards the realization of on-chip integrated nanophotonic devices but also opens the possibility of the construction of ultrahigh-speed information processing chips based on plasmonic circuits.

On-chip plasmon-induced transparency based on plasmonic coupled nanocavities

On-chip plasmon-induced transparency offers the possibility of realization of ultrahigh-speed information processing chips. Unfortunately, little experimental progress has been made to date because it is difficult to obtain on-chip plasmon-induced transparency using only a single meta-molecule in plasmonic circuits. Here, we report a simple and efficient strategy to realize on-chip plasmon-induced transparency in a nanoscale U-shaped plasmonic waveguide side-coupled nanocavity pair. High tunability in the transparency window is achieved by covering the pair with different organic polymer layers. It is possible to realize ultrafast all-optical tunability based on pump light-induced refractive index change of a graphene cover layer. Compared with previous reports, the overall feature size of the plasmonic nanostructure is reduced by more than three orders of magnitude, while ultrahigh tunability of the transparency window is maintained. This work also provides a superior platform for the study of the various physical effects and phenomena of nonlinear optics and quantum optics.

Ultralow-power and ultrafast all-optical tunable plasmon-induced transparency in metamaterials at optical communication range

Actively all-optical tunable plasmon-induced transparency in metamaterials paves the way for achieving ultrahigh-speed quantum information processing chips. Unfortunately, up to now, very small experimental progress has been made for all-optical tunable plasmon-induced transparency in metamaterials in the visible and near-infrared range because of small third-order optical nonlinearity of conventional materials. The achieved operating pump intensity was as high as several GW/cm2 order. Here, we report an ultralow-power and ultrafast all-optical tunable plasmon-induced transparency in metamaterials coated on polycrystalline indium-tin oxide layer at the optical communication range. Compared with previous reports, the threshold pump intensity is reduced by four orders of magnitude, while an ultrafast response time of picoseconds order is maintained. This work not only offers a way to constructing photonic materials with large nonlinearity and ultrafast response, but also opens up the possibility for realizing quantum solid chips and ultrafast integrated photonic devices based on metamaterials.

A Historical Perspective of Technology and Planning

Technology is our savior. We see, hear and experience this mes- sage constantly in popular culture, from advertisements that demon- strate how technological gadgets make us smarter and perhaps even more likable to forecasts by financial analysts that the information economy will continue to increase wealth for savvy investors. The hype produced by this common message implies that unless we jump on the information age bandwagon, we risk missing out on its vast benefits. Futuristic writers such as Alvin Toffler, Bill Gates, and Nicho- las Negroponte proclaim the arrival of a digital age, in which the conditions of home, work and play are greatly enhanced through the omnipresence of information processing chips in all facets of life. As Christine Boyer puts it, computer technology has become such an important part of life for some people, a way of life that “has bred its own form of transcendental utopianism”.

Thermal properties of lanthanum modified lead zirconate titanate (PLZT), lithium niobate and lithium tantalate

Abstract Fabrication of optical information processing chips involves a lot of thermal processing with silicon and electro-optic material. The information of thermal properties becomes important in this technology. Thermal conductivity, thermal diffusivity and specific heat of ceramic lanthanum modified lead zirconate titanate (PLZT), single crystal lithium tantalate (LiTaO3) and lithium niobate (LiNbO3) have been measured. Measurements were made over various temperature ranges (up to 400°C). The techniques used to make the measurements are described. Comparison is made to available data.