Journal Club 2022 | Tanabe Photonic Structure Group

Journal Club

By fiscal year (April-December)

Fiscal Year 2022

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A photonic analog of twisted bilayer graphene that has ultra-flat photonic bands and exhibits extreme slow-light behavior.

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2020Since the turnkey soliton was realized inThe practical application of soliton com has become even more realistic.To ensure future scalability, theCMOSCo-use of compatible materialsVibrators are indispensable. Among them, soliton combsilicon carbide(SiC)has long been widely used as a semiconductor material.contract manufacturerOSCompatible materials.SiCis the same asRelatively large refractive index when compared to silicon nitride(n=2.6)and nonlinear refractive index(n₂=8.6x10^-8 m²w^-2)and hasNonlinear optical effects at lower power can be expected. However, theAs for the application to soliton combs, the thermo-optical coefficient is large andgreenhouseThere has never been an example of such a system at high temperatures. Therefore, we have developed theUsing the assisted laser methodgreenhouseDue to the achievement of soliton com generation at temperaturesThe following is a report.

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Optical parametric oscillation is,Coherent laser light at frequencies well away from the pump frequency.Although it can be generated,For practical use, the conversion efficiency from pump to signal is,It needs to be much higher than what has been demonstrated so far.To address this issue,Parametric oscillation in Kerr nonlinear micro optical resonators from theoretical andbeautifully and numericallystudyResearch,Reveals complex solution spaces arising from the interaction of nonlinear processes.First,3Using mode approximation,Derive the relationship between pump power and frequency mismatch efficiency maximization.However,Realistic devices such as integrated microring resonators are,3since (a time in the past)Because it supports the above modes,A more accurate model that includes the entire mode,To determine potential efficiencies arising from unwanted competing nonlinear processesIt is necessary For this purpose,Considering the full spectrum of nonlinear coupled resonator modesLugiato-LefeverThe equation was calculated.Related to parametric oscillation in multimode resonators2Two non-linearForm Phenomena,i.e., modulation by mode contention and cross-phase modulationObserve and characterize the instability. Finally,By adjusting the loss factor of the micro resonator, the conversion efficiency can be reduced to about25%The method is shown how to increase it to This analysis is,Design pointers for microresonators aiming for high conversion efficiency and output powerIt is a needle.

Nature Electronics 5, 184-190 (2022).
A. M. J. Zwerver, T. Krähenmann, T. F. Watson, L. Lampert, H. C. George, R. Pillarisetty, S. A. Bojarski
B. P. Amin, S. V. Amitonov, J. M. Boter, R. Caudillo, D. Correas-Serrano, J. P. Dehollain, G. Droulers
E. M. Henry, R. Kotlyar, M. Lodari, F. Lüthi, D. J. Michalak, B. K. Mueller, S. Neyens, J. Roberts
N. Samkharadze, G. Zheng, O. K. Zietz, G. Scappucci, M. Veldhorst, L. M. K. Vandersypen & J. S. Clarke

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Realization of a full-scale quantum computer with error correction requires hundreds ofmillion qubits are required, andQuantum co using semiconductor qubits with industrial semiconductor fabrication technologyComputers have high potential in this area.
However, theCurrently reported methods for fabricating semiconductor qubits are electron beam lithographyThe production process is not high-yield, as it is made by a process that uses a large number of materials.
(somebody's) sidestudyIn the study, theUsing photolithography techniques used in the manufacture of today's industrial products，Semiconductors on chips on 300 mm wafers produced in a fully industrial manner.The body qubits were confirmed.
This has dramatically improved the yield rate.

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Chaotic dynamics has been reported in many physical systems and has affected almost every field of science. Thus, it is often unwanted. Interestingly, the very same features make chaos a powerful tool to suppress decoherence, achieve secure communication and replace background noise in stochastic resonance-a Here, we report the first demonstration of chaos-induced stochastic resonance-a counterintuitive concept that a system's ability to transfer information can be coherently amplified by adding noise. demonstration of chaos-induced stochastic resonance in an optomechanical system, as well as the optomechanically mediated chaos transfer between two These results will contribute to the understanding of nonlinear phenomena and chaos in These results will contribute to the understanding of nonlinear phenomena and chaos in optomechanical systems, and may find applications in the chaotic transfer of information and for improving the detection of otherwise undetectable signals in optomechanical systems.

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The sixth generation (6 G) communication standard is expected to include support for very-high data rates (over 100 Gbit/s) and device electronics will Although the terahertz band possesses ample bandwidth, conventional THz waveguides suffer from high bending losses and are sensitive to process defects. The recent revelation of the topological valley photonic crystal (VPC), the topological valley photonic crystal (VPC), which exhibits near zero-loss bends, zero back-scattering and zero junction-area, holds much promise for future high speed inter-device communications. In this article, low dispersion in the photonic bandgap region as the number of bends increase is demonstrated through In this article, low dispersion in the photonic bandgap region as the number of bends increase is demonstrated through simulation and experiment of the transmission and group delay characteristics. A 108-Gbit/s bit rate using multi-level modulation for a 10 mm straight VPC waveguide and a 62.5-Gbit/s bit-rate for a ten sharp bended structure is demonstrated through comprehensive communications experiments.

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Optical integrated circuits in the visible light range are,ARand ... andVRdespray, quantum computation, sensing, optogenetics, etc,Many applications are expected. Among optical integrated circuits, optical phase modulators are,It is an essential element in achieving them. However, the existingcontract manufacturerOSIntegrable phase modulators in the visible light range that can be realized using technologyare several hundred in size.umand half-wavelength power in the tens.mWAnd,It is currently far from practical. Therefore, in this study,Using silicon nitride micro optical resonators,530nmobi and488nmUltra-small andWe have realized an ultra-low power consumption optical phase modulator and introduce it here.

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Higher-order seed modulation instability experimentally in fiber optic experimentsThe study was conducted. The loss-compensated recirculation loop configuration allows for a complex andThe spatio-temporal evolution of the initial modulation continuous field, which exhibits deterministic dynamics, isSingle-shot observation is possible. The modulation period can be adjustedand thus, fully coherent dynamics and pure noise-drivenA continuous transition between the dynamics is observed, and furthermore, statistical methodsThe characteristics were clarified by

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Coupling between waveguides is a common phenomenon in optics, and it is a common phenomenon in the control of light paths.and integration. In addition, the coupling properties areVery sensitive to wavelength and waveguide structure, broadband and resistant to manufacturing errorsIt is difficult to achieve path coupling. In this study, we use a population gauge field (artificial gauge field (AGF) to enable the design of coupling dispersion, and to provide a wide bandwidth and manufacturing error tolerantThe waveguide with a

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Despite the impressive results with current integrated lasers, the actualThere are several problems that remain in the application of the system. One of them is the frequency tuning.The first is the electro-optic modulation of the III-V group and silicon. Conventional electro-optic modulation of III-V and siliconFrequency tuning at the MHz level is possible, but thermo-optical effects and shifts in carrier density and optical modeThis limited the performance. In this study, we investigated the effect of II-V/niobate2 exahertz/sec (2.0 x 10) using a hybrid integrated structure of lithium¹⁸ The highest ever frequency modulation speed of 50 MHz (Hz/second) and the highest speed of 50 MHz (50 Hz/second) are achieved.It is an integrated laser with itching. In addition, the Pockels effect enables simultaneous transmission of infrared and visible light.The world's first integrated multi-color laser.

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With advances in photonic integration technology, chip-scale high-frequency (RF) filter development has become very important. In this study, a soliRequires pulse shaping using a smooth spectral envelope of tons andSoliton microcomb-based high-frequency photonic filters withoutDemonstration. A system that combines multiple wavelength light sources and dispersion propagation is tappedIt functions as a delay line with delay (TDL) filter and is used in the FIR filter structure.The structural complexity is greatly reduced. The light source is a perfect soliton crystal (PSC) can be used to divide the RF transmission bandwidth, andand to properly control the relative azimuth angles of the two interfering solitons.The filter reconstruction was achieved by

Nature Photonics (2022)
Gia Quyet Ngo, Emad Najafidehaghani, Ziyang Gan, Sara Khazaee, Malte Per Siems, Antony George, Erik P. Schartner, Stefan Nolte, Heike Ebendorff-, Heidepriem, Thomas Pertsch, Alessandro Tuniz, Markus A. Schmidt, Ulf Peschel, Andrey Turchanin & Falk Eilenberger Heidepriem, Thomas Pertsch, Alessandro Tuniz, Markus A. Schmidt, Ulf Peschel, Andrey Turchanin & Falk Eilenberger

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Silica-based optical fibers are the mainstay products of nonlinear optics,Immediate access to a variety of nonlinear phenomena such as solitons and self-phase modulation.You can access the server. However, there is one fundamental limitation. Silica is amorphous,Unless the influence from the surface is negligible,It does not exhibit second-order nonlinearity. Here,MoS2 with high nonlinearity grown directly on the core of the fiber.Using a single layer,Shows the generation of the second harmonic in a functionalized optical fiber.Fibers functionalized with MoS2 have a 44 pmV^-1Secondary susceptibility ( χ (2)) values and 0.2 × 10^-3 m^-2W^-1The second harmonic generation conversion efficiency ofThis approach is scalable,Can be generalized to other transition metal dichalcogenides and a wide range of waveguide systemsWe do. Our results,New approach to second harmonic sources in efficient fibershows χ(2)-based nonlinear optical fiber,Optoelectronics, Photonics Platform,Integrated Optical Architecture,and active fiber network platforms.The possibility exists that the company may be able to stand on its own feet.

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Erbium ion-based optical amplification has been studied in optical integrated circuits.However, the output was not sufficient for practical use. In this studyachieved an output power of 145 mW and a small-signal gain of more than 30 dB with an erbium amplifier using a silicon nitride waveguide. This is the output power of the soliton com100 times, and can be applied to low-noise optical microwave generation and wavelength-division multiplexed communications.The value is practical.

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Nonlinear optical effects are used in all-optical calculations and photonic neural networksThe light source is expected to have a variety of applications, such as ultrafast light sources on substrates. However, few of these applications have been realized in the past.Nonlinear optical effects are not large for most photonic materials, and largeThe use of a resonator with high operating energy and high Q-value was necessary.In this study, all light without resonators due to strong second-order nonlinear optical effectsAn optical switch was developed to achieve high speed and low power consumption. In addition, the company has developed a distributedThe spatial and temporal pulse shape is successfully maintained by theThe following is a list of the most common problems.

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Presentation: Hybrids combining two materials with opposite thermo-optical coefficientsAssuming a 3d Si3N4-TiO2 microring resonator, the thermo-refractiveNon-thermal structures that cancel the effect are studied theoretically.Numerical results show that under appropriate parameters, the thermo-refractive effect can be reducedand under these conditions the soliton state can be easily accessed.The results revealed that the micro optical resonator and the surrounding environment can be used as a thermal interface. The thermal interaction between the micro optical resonator and the surrounding environment is alsoThe thermo-refractive noise produced by the conversion is also suppressed by one order of magnitude, and the spectralOptical clocks, microwave generation, and other potential applications of soliton comThe results of this study showed that it is extremely important for

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In recent years, studies on the generation of cur-solitons and coherent frequency combsis actively being done, the Kerr (third-order) nonlinearity is intrinsically weak, and theParametric oscillation thresholds require high Q resonatorsThe present study is based on the second-order nonlinearity-based degenerate optical parametric Therefore, in this study, we propose a second-order nonlinearity-based degenerate optical parametricThe time so called induced by the walk-off in the oscillator (DOPO).Demonstrate the lithon. Significant temporal walk-off between pump and signalDissipative second-order solitons by non-stationary optical parametric amplification in the presenceformation was demonstrated, and strong second-order nonlinearities resulted in picodule-level ponThe results show that significant pulse compression is possible in theThese results include wavelength conversion, wavelength diversity, and resonator finesse requirements.The realization of solitons using pure second-order nonlinearities with practical advantages.It is a cooperative effort.

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For photonic device and system performance,Control of material structure is essential.The optical separation of the photonic material from the substrate is,Although they can significantly improve their performance,They suffer from complex manufacturing processes and limited applications.Here, the polymer bilayer (EOB)Free-standing photo based on one-step electron beam direct writing toTo manufacture nick structures,A differential polymer chain scission strategy is proposed.By the sensitivity of the polymer to the electron beam, which depends on the molecular weight of the polymer,It allows for different patterning of the two layers of polymer,Suspended micro optical resonators are directly formed. the EOB technology,Micro optical resonators feature high material compatibility and design flexibilityBy this,The range of applications for suspended micro-optical resonators is greatly expanded.The results are a versatile strategy for building high-performance photonic materialsIn addition to providingPromising plat for innovative applications in optical microstructuresform.

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Active metasurfaces promise reconfigurable optics with drastically improved compactness, ruggedness, manufacturability and functionality Optical phase-change materials (PCMs) offer an appealing material solution for active metasurface Here we report a large-scale, electrically reconfigurable non-volatile The optical PCM alloy used in the devices, Ge2Sb2Se4Te (GSST), uniquely combines giant non-volatile The optical PCM alloy used in the devices, Ge2Sb2Se4Te (GSST), uniquely combines giant non-volatile index modulation capability, broadband low optical loss and a large reversible switching volume, enabling notably enhanced light -Capitalizing on these favourable attributes, we demonstrated quasi- Capitalizing on these favorable attributes, we demonstrated quasi- continuously tuneable active metasurfaces with record half-octave spectral tuning range and large optical contrast of over 400%. We further prototyped a polarization-insensitive phase-gradient metasurface to realize dynamic optical beam steering.

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On surface changes of optical micro- and nanofibers (MNFs)The research linking the two is still in its early stages, and the original mechanism reported is still in its early stages.It has remained a mystery for many years. In this paper,Fiber heating, mechanical tapering, and high power pulses in MNFby considering the combined interaction of slaser waveguiding processes,The general thermo-mechanical-photo activation mechanism that can explain the surface changes of MNFs.Established. Bonding ene by fiber heating and mechanical tapering.The silicon-oxygen bonding is assumed to increase significantly.The energy required to cleave the coupling into a gluing bond is the intrinsic bandgapThe output pulse rate is significantly reduced from about 9eV in the first half to about 4.0eV in the second half, and the high output pulse rate is reduced to about 4.0eV in the third half.The laser induces obvious surface changes in MNFs by multiphoton absorption.It was found that the Finally, the surface of MNFs with surfactantsto nonlinear optics from sensing and optoelectronics by restoring theIt has demonstrated that it can be used for promising applications all the way up to and includingThese results will be used to prevent future performance degradation and for practical MNF device applications.It opens the way.

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Parametric amplifiers have been an important part of physicsHowever, current parametric amplifiers have high gain and low power consumption. However, current parametric amplifiers have high gain andNo one has achieved both low noise andNew devices that can satisfy both of these needs are being sought.In this research, we have developed a parametric amplifier using a semiconductor superlattice that can be used in the world.The first demonstration of this technology in the world was conducted.

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Photonic Crystal (PhC) and Whisper Gallery Mode (WG)(M) concept, we introduce a gear-like PhC ring resonator.The "microgear" photonic crystal ring (MPhCR) is a photonic crystal ring with a large number of photons. This "microgear" photonic crystal ring (MPhCR)is a periodic modulation on the inner boundary of a microring resonator, such as a PhC resonator.and circularly symmetric like a WGM resonator.The outer boundary of the dielectric band and the high Q-value of the dielectric band are both excellent. The dielectric band edge is a slow-light devaThe Q-value is about 50 times higher than that of the recording of theA mode was observed in which the group velocity was 10 times slower than that of the slower mode. Furthermore, this slowWGM is localized in the defective mode of PhC as a starting point for the design of the PhC light.By reducing the mode volume by a factor of 10 or more compared to the conventional WGM, the maximum mode volume (up to(5.6 ± 0.1) × 10⁵MPhCR strongly controls fundamental photonic crystal properties such as group velocity and localizationThis provides an exciting platform for a wide range of photonics applications, including sensing and metrology, nonlinear optics, and Cavity QED.The following is a brief description of the process.

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In contrast to the bright solitons that occur in the anomalous dispersion region, the normal dispersionObservations of dark solitons generated in micro optical resonators in the region reportedThe dark soliton generation is a key to the design of free dispersion and thermal instability. The generation of dark solitons requires free dispersion design and thermal instability.The advantage of this method is that it is less affected by the qualitative characteristics. In this paper, we present a micro-optical coWe report on the coupling state of darkbright soliton pairs in theThe two modes with opposite dispersions and equal group velocities are excited. Two modes with opposite dispersions and equal group velocities are excited, and the bryDue to Kerr induced cross-phase modulation (XPM) caused by a solitonPassively generates dark solitons. Dark by micro optical resonatorThe generation of bright soliton pairs is unprecedented and is similar to a frequency comb.It exhibits the interesting property of having a constant output while having a pectThe results are useful for applications such as telecommunication systems and ultrahigh-speed optics. These results are useful for applications such as telecommunication systems and ultrahigh-speed optics.The following table shows the results of the analysis.

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Multispectral photodetectors are used to detect visible (VIS), near redOutside line (NIRNew devise. The image data acquired by these photodetectors is used for human visualEffective object with additional information beyond sensory information, including thermal imaging and night visionfor identification and navigation. However,These functions arise from the coupling of multiple heterojunctions and selective absorbersThe complexity of the structure is hindered by the complexity of the structure. In this study,Ge/MoS2Photovoltaic and photodetector with a van der Waals heterojunction photodetector.and photoconduction in a mode close to photoconduction.VISandIRSelective detection functionality is implemented.The following is an example of a simple, single-polarity bias using a single pixel. Simplified single-polarity bias using a single pixelThe operation greatly reduces the complexity of the structure, and the multispectral selectiveMinimize peripheral circuits for detection.The multispectral photodetector in this study is automatically operated and monitored,Applicable to computer vision and biomedical imagingskillfulVIS/NIRPotential avenues for visual integration.

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What is Journal Club?
This is an open lecture series held in Tanabe Photonic Structures Laboratory. Students who are graduate students or above will survey papers related to optics and related technologies such as photonics, materials, bioscience, etc., and explain them in an easy-to-understand manner.

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Nature Electronics 5, 184-190 (2022).
A. M. J. Zwerver, T. Krähenmann, T. F. Watson, L. Lampert, H. C. George, R. Pillarisetty, S. A. Bojarski
B. P. Amin, S. V. Amitonov, J. M. Boter, R. Caudillo, D. Correas-Serrano, J. P. Dehollain, G. Droulers
E. M. Henry, R. Kotlyar, M. Lodari, F. Lüthi, D. J. Michalak, B. K. Mueller, S. Neyens, J. Roberts
N. Samkharadze, G. Zheng, O. K. Zietz, G. Scappucci, M. Veldhorst, L. M. K. Vandersypen & J. S. Clarke

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