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Conference 13349
Laser Resonators, Microresonators, and Beam Control XXVII
28 - 29 January 2025 | Moscone South, Room 207 (Level 2)
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Session 1:
Novel Microdevices I
28 January 2025 • 8:30 AM - 9:55 AM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Vladimir S. Ilchenko, Jet Propulsion Lab. (United States)
13349-800
28 January 2025 • 8:30 AM - 8:35 AM PST | Moscone South, Room 207 (Level 2)
13349-1
28 January 2025 • 8:35 AM - 8:55 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
This paper proposes a frequency-swept feedback interferometry(FSFI) ranging method based on resonant cavity enhancement for long-distance non cooperative target measurement and weak signal detection. The method uses target feedback light and local oscillator light to interfere in the laser resonant cavity to generate an interference signal containing target distance information. The output laser is then converted into a frequency modulation signal through a Mach Zehnder interferometer (MZI) to further improve the signal-to-noise ratio(SNR) of the interference signal.
13349-2
28 January 2025 • 8:55 AM - 9:15 AM PST | Moscone South, Room 207 (Level 2)
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A novel method is used to fabricate state-of-the-art micro-mirrors at wafer scales, with the radius of curvature (ROC) in the range of 90 um ~ above 700 um, and a finesse of over 3.3 x10^5 at 780 nm. They form robust microcavities suitable for laser stabilization and for studying neutral atom cavity quantum electrodynamics (QED).
13349-3
28 January 2025 • 9:15 AM - 9:35 AM PST | Moscone South, Room 207 (Level 2)
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Our team has developed an advanced green enhancement cavity for a compact synchrotron X-ray source based on Compton scattering. Since the X-ray energy generated by scattering of laser photons from highly-relativistic electrons is proportional to the laser photon energy, this doubles the maximum X-ray energy. This enhancement significantly improves the analysis of dense, absorbent, and thick specimens, such as human bones or archaeological samples, addressing the need for better diagnostic capabilities and a more widespread availability of synchrotron radiation in these fields. The green enhancement cavity, which we have already built and refined, functions effectively, promises a high stored optical power and compatibility with the electron storage ring's vacuum requirements. This presentation details the successful design and performance validations of the green cavity highlighting its significant impact on X-ray production and material analysis.
13349-4
28 January 2025 • 9:35 AM - 9:55 AM PST | Moscone South, Room 207 (Level 2)
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Cascaded meta-optics have enabled complex wavefront shaping beyond their single layer counterpart owing to the additional design variables afforded by each plane. For instance, complex amplitude modulation, generalized polarization transformations, and wide field of view are key attributes that fundamentally require multi-plane wavefront matching. Nevertheless, existing embodiments of bilayer metasurfaces have relied on configurations which suffer from Fresnel reflections, low mode confinement, or undesired resonances which inevitably compromise the intended response. We review recent progress in this area and introduce the first bilayer metasurface made of free-standing titanium dioxide meta-atoms in the visible regime. We demonstrate its use in wavefront shaping of linearly polarized light using pure geometric phase with diffraction efficiency reaching 80% — expanding previous literature on Berry phase metasurfaces which often assumed circularly polarized illumination. We discuss the potential of this configuration in structured light generation, integration on chip, imaging and polarization control.
Break
Coffee Break 9:55 AM - 10:25 AM
Session 2:
Microcavity Sensors
28 January 2025 • 10:25 AM - 12:00 PM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Qing Gu, North Carolina State Univ. (United States)
13349-5
28 January 2025 • 10:25 AM - 10:45 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Frequency-modulated continuous wave (FMCW) LIDAR has provided a path toward high-resolution optical ranging and velocity measurements, which, compared to time-of-flight LiDAR, exhibits inherent robustness to ambient light and nearby LIDAR systems, and simultaneous distance and velocity measurement. Although recent work has addressed an existing constraint of frequency-domain detection using a direct time-domain peak detection scheme, using electro-optic (EO) frequency combs, such schemes are typically limited by the phase noise of the EO comb.
Here, we experimentally propose a new scheme for LiDAR leveraging CMOS-compatible microresonator-based optical frequency combs (OFCs). We rely on the all-optical mechanism of Kerr-induced synchronization of a dissipative Kerr soliton to a reference laser, thus eliminating the influence of on-chip thermo-refractive noise on the OFC. Our scheme allows for fast time-domain detection and low-noise operation, over a large spectral window in the bandwidth of the OFC. This has potential applications beyond ranging, including sensing, spectroscopy and communications.
13349-6
28 January 2025 • 10:45 AM - 11:10 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Optical parametric amplifiers (OPAs) utilize the nonlinearities of optical materials for gain generation, enabling signal amplification across a wide range of wavelengths, operating unidirectionally, and facilitating very large optical gain over a substantial bandwidth and noise-less, i.e. phase-sensitive optical amplification. Despite the marquee breakthroughs achieved with highly nonlinear optical fibers in the early 2000s, commercial adoption has been hampered by the requirements for very long fiber length, mitigation of parasitic nonlinearities, and high pump powers. Photonic integrated waveguides combine much stronger optical confinement with a stronger Kerr nonlinearity and the ability to precisely low engineer the optical dispersion over a wide wavelength range yet have suffered from high linear and nonlinear optical propagation losses and low power handling capacity, mandating pulsed operation. In this presentation, I will review recent work on the breakthrough of achieving strong, broadband, and time-continuous travelling wave parametric amplification in photonic integrated circuits based on silicon nitride and gallium phosphide.
13349-7
Microresonators for sub-nanoradian resolution
(Invited Paper)
28 January 2025 • 11:10 AM - 11:35 AM PST | Moscone South, Room 207 (Level 2)
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Phase measurements are quantum limited by the phase-photon-number uncertainty relation. One example is the laser gyroscope, where the Sagnac phase shift is converted into a frequency. The same principle of converting phase into frequency applies inside a linear mode-locked laser cavity, with which we demonstrated a resolution of 0.4 nanoradian, or 0.1 fm in optical pah. It is shown that this resolution can be improved by miniaturization, and applied to accelerometry and magnetometry.
13349-8
Rare-earth ion doped Al2O3 for on-chip lasers
(Invited Paper)
28 January 2025 • 11:35 AM - 12:00 PM PST | Moscone South, Room 207 (Level 2)
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Rare-earth ions doped into different host materials can provide optical amplification with excellent performance parameters thanks to their long intrinsic lifetime. In this work, we will give an overview of our recent developments on rare-earth ion doped Al2O3 deposited by reactive sputtering including both erbium and thulium ion doping for operation in the C-band and in the 1800-2000 nm band.
Break
Lunch/Exhibition Break 12:00 PM - 1:45 PM
Session 3:
Microcombs I
28 January 2025 • 1:45 PM - 3:35 PM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Andrey B. Matsko, Jet Propulsion Lab. (United States)
13349-9
28 January 2025 • 1:45 PM - 2:05 PM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
More complex stationary waveforms than single solitons, such as soliton
molecules and soliton crystals, have been the subject of extensive experimental study in
both fiber lasers and microresonators. However, their stability in the presence of noise on
a timescale that can be observed in a laboratory experiment (from milliseconds to seconds) has been difficult to calculate. Here, we introduce a synergetic simulation method
that makes it possible to take time steps that are many orders of magnitude larger than with
conventional methods and to determine both the waveform dynamics and stability in the
presence of noise on a laboratory timescale. We apply this method to a stable two-soliton
molecule in a microresonator system to carry out Monte Carlo simulations and determine
when the molecule becomes unstable. We validate the model and then apply it to more
complex waveforms.
13349-10
Existence, stability, and characteristics of pure-Kerr parametrically driven cavity solitons
(Invited Paper)
28 January 2025 • 2:05 PM - 2:30 PM PST | Moscone South, Room 207 (Level 2)
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We have recently unveiled – both theoretically and experimentally – a new paradigm of dissipative soliton frequency comb generation that can be achieved in coherently-driven Kerr resonators [G. Moille et al., Nature Photonics 18, 617–624 (2024)]. Here, a judiciously dispersion-engineered resonator is driven with two monochromatic lasers with large frequency separation, giving rise to a cavity soliton frequency comb with carrier frequency in between the two inputs via parametric four-wave-mixing. In this presentation, we will discuss the existence, stability, and characteristics of the resultant pure-Kerr parametrically-driven cavity solitons.
13349-11
28 January 2025 • 2:30 PM - 2:50 PM PST | Moscone South, Room 207 (Level 2)
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We investigate the impact of the frequency drift of a laser cooler on the phase noise of the repetition rate of a bright soliton microcomb generated in an Si3N4 microring resonator using the auxiliary laser cooling scheme. We find that below a 1-kHz offset from the carrier, the repetition rate phase noise of the generated microcomb is dominated by the frequency drift of the cooler under the free-running condition.
13349-12
28 January 2025 • 2:50 PM - 3:10 PM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
In this work, we theoretically, numerically, and experimentally demonstrate that all-optical trapping of a Dissipative Kerr-Soliton (DKS) does not necessarily result in the direct capture of a comb tooth from the auxiliary laser. Instead, DKS Kerr-induced synchronization (KIS) can result from the parametric interaction between two auxiliary lasers. Similar to the generation of parametric cavity solitons, the nonlinear mixing of the auxiliary lasers provides an additional parametric force to the DKS, which, once its phase is close enough to the DKS's, triggers synchronization. Our work extends the range of use for KIS, enabling soliton trapping to occur outside the fixed frequency grid imposed by the soliton microcomb.
13349-13
Enhancing tunability and conversion efficiency of Kerr soliton microcombs in crystalline microresonators
(Invited Paper)
28 January 2025 • 3:10 PM - 3:35 PM PST | Moscone South, Room 207 (Level 2)
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In this presentation, we will discuss our recent advancements in the development of soliton microcombs in ultrahigh-Q crystalline microresonators. We emphasize significant improvements in both the tunability and conversion efficiency. Through sophisticated dispersion engineering and the implementation of frequency stabilization techniques, we have opened new avenues for practical applications and fundamental studies in soliton physics.
Break
Coffee Break 3:35 PM - 4:05 PM
Session 4:
Microcombs II
28 January 2025 • 4:05 PM - 5:35 PM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Andrea M. Armani, The Univ. of Southern California (United States)
13349-14
Quadratic bright and dark solitons in on-chip degenerate optical parametric oscillators
(Invited Paper)
28 January 2025 • 4:05 PM - 4:30 PM PST | Moscone South, Room 207 (Level 2)
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Temporal Kerr cavity solitons in passive optical resonators have attracted significant attention over the last decade. After being demonstrated on several platforms, hybrid Kerr architectures have appeared to increase conversion efficiency or energy extraction. Another approach is to rely on second-order nonlinearity to generate solitons. Such quadratic cavity solitons offer two main advantages over their Kerr counterparts: reduced pump powers and frequency combs formation far away from the pump frequency. In my talk, I will present our recent investigations of two types of quadratic solitons in an on-chip degenerate optical parametric oscillator, leveraging the recent advances in lithium niobate nanophotonic. The first one is the topological soliton, arising from the locking between domain walls. The second one is a sech-squared cavity soliton, found when a slight phase mismatch is introduced. These results constitute a first step towards broadband frequency combs in quadratic resonators with low finesse and normal dispersion.
13349-15
28 January 2025 • 4:30 PM - 4:55 PM PST | Moscone South, Room 207 (Level 2)
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We demonstrate that Kerr-induced synchronization (KIS) strongly damps the impact of intrinsic noise sources on the repetition rate of microcombs. We analytically and numerically calculate the theoretically achievable microcomb repetition rate noise floor in the presence of thermorefractive noise (TRN). We experimentally demonstrate that noise levels below the TRN limit can be achieved using KIS even with free-running lasers. Thus, we show that KIS enables small microresonators, which are advantageous for octave-spanning microcomb operation, to potentially reach noise limits on par with their larger counterparts.
13349-16
28 January 2025 • 4:55 PM - 5:15 PM PST | Moscone South, Room 207 (Level 2)
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We speed up the dispersion engineering of octave-span soliton microcombs with an advanced parameter-search algorithm and analytical model. With systematic parameter scans in wafer-scale and integrated-photonics foundry, we realize its single-chip solutions. The dispersive-wave mode-switching phenomena, caused by nonlinear self-interactions of few-cycle solitons, allows for post-fabrication tuning of the dispersive-wave frequencies, yielding sufficient signal-to-noise ratio in carrier-envelope offset frequency detection. We further utilize photonic crystal resonators to streamline the challenging soliton generation. This nano-pattern sidewall modulation couples the counter-propagating waves and reduce the power difference between bistable states, during the transition from chaos state to the soliton state, which enables spontaneous soliton generation without complex fast detuning sweep. Our designs and experiments facilitate microcomb spanning from 780 nm to 2200 nm with pump laser wavelengths at 1064 nm and 1550 nm.
13349-17
28 January 2025 • 5:15 PM - 5:35 PM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
We report the observation of soliton self-injection locking (SIL) to fiber Fabry-Pérot (FFP) resonator with a laser pump power of less than 100 mW. The locking process is studied analytically with a model of a Fabry-Pérot laser interacting with an external FFP and the modelling results are compared to the experimental ones. The model was then developed for a nonlinear FFP modifying, due to the tilt of the resonance with self-phase modulation, the frequency response of the laser. Experimentally, we obtain a large locking range with direct access to primary combs, chaotic combs and soliton while keeping a stable laser lock.
Posters-Tuesday
28 January 2025 • 6:00 PM - 8:00 PM PST | Moscone West, Room 2003 (Level 2)
Conference attendees are invited to attend the Tuesday LASE poster session. Come view the posters, enjoy light refreshments, ask questions, and network with colleagues in your field. Authors of poster papers will be present to answer questions concerning their papers. Attendees are required to wear their conference registration badges to the poster sessions.
Poster Setup: Tuesday 10:00 AM - 5:00 PM
Poster authors, view poster presentation guidelines and set-up instructions at https://spie.org/PWPosterGuidelines
Poster Setup: Tuesday 10:00 AM - 5:00 PM
Poster authors, view poster presentation guidelines and set-up instructions at https://spie.org/PWPosterGuidelines
13349-35
28 January 2025 • 6:00 PM - 8:00 PM PST | Moscone West, Room 2003 (Level 2)
Show Abstract +
A multichannel Shack-Hartmann wavefront sensor can be used to measure the wavefront of four independent high-power laser beams. The wavefront sensor with the single physical sensor can be used in order to simplify the experimental setup and hardware control. In this research we discuss the development of the four-channel single-sensor high-resolution Shack-Hartmann metrology device for wavefront sensing. The whole sensor area of 15×15 mm was divided into 4 logical apertures, each of which measures the wavefront of a separate high-power laser beam. The development and calibration procedure are described. The wavefront sensor control software is developed and tested.
13349-36
28 January 2025 • 6:00 PM - 8:00 PM PST | Moscone West, Room 2003 (Level 2)
Show Abstract +
Atmospheric turbulence causes refractive index fluctuations that introduce extra distortions to the wavefront of the propagated radiation. It degrades the resolution of the telescope for imaging applications and reduces the radiation power density in focusing applications. In this paper, we developed the adaptive optical system with the bimorph deformable mirror and tip-tilt corrector. The whole system is controlled by the software that runs on standard PC. The frequency of the closed loop is from 600 Hz up to 1000 Hz depending on the performance of the CPU.
13349-37
28 January 2025 • 6:00 PM - 8:00 PM PST | Moscone West, Room 2003 (Level 2)
Show Abstract +
One common effect in semiconductor quantum dots (QDs) is high Auger recombination rate, which is harmful to many of its applications, including lasing. Here, the potential surface is smoothed to promote alloy formation at the core-shell interface, thereby reducing the auger recombination rate of CdZnSe /CdS QDs. In addition to reduced Auger recombination rate, the synthesized CdZnSe/CdS QDs exhibit o a large Stoke's shift eliminating the problem of reabsorption. In order to achieve plasmonic-assisted absorption enhancement and support overall emission enhancement, AgNPs are selected so that their absorption profile overlaps with CdZnSe /CdS QDs. Conversely, Whispering gallery mode (WGM) resonators provide remarkable optical amplification due to their high Q-factor and low optical losses. While the use of pulsed lasers facilitates lasing, optoelectronic device integration has proven to be more challenging. Despite being a good substitute, CW lasers are not practical because of their low instantaneous power density. Here, a micro-neck fiber structure made of Ag NP-PVA composite and the QDs has been used to realize effective WGM lasing with CW excitation using CdZnSe/CdS colloidal qua
13349-38
28 January 2025 • 6:00 PM - 8:00 PM PST | Moscone West, Room 2003 (Level 2)
Show Abstract +
We demonstrate that Kerr-induced synchronization (KIS) enables multi-dissipative Kerr solitons (multi-DKSs) to achieve similar noise performance as single DKSs, by removing relative jitter between the soliton pulses due to the shared all-optical trapping potential. Since multi-DKS states enable higher pump conversion efficiency and more thermally stable low noise microcomb operation in comparison to their single DKS counterparts, this work represents a significant leap in the practical applications of chip-scale frequency combs.
13349-39
28 January 2025 • 6:00 PM - 8:00 PM PST | Moscone West, Room 2003 (Level 2)
Show Abstract +
This paper presents the design of a deformable mirror with a compact arrangement of piezoactuators. Thermal stabilization of the substrate with a mirror coating is realized through the basement. Piezoactuators use a pre-mechanical loading mechanism that provides a symmetrical stroke of +-3.5 microns. It is possible to replace a failed piezostack with a new one.
13349-40
28 January 2025 • 6:00 PM - 8:00 PM PST | Moscone West, Room 2003 (Level 2)
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The paper presents the dependence of the level of quantum bit error rate (QBER) during the propagation of laser radiation through an atmospheric turbulent medium in three regimes: without introducing wavefront distortions, with the generation of artificial turbulence using a fan heater, and in the mode of correcting wavefront aberrations using a bimorph deformable mirror with a diameter of 50 mm with 31 control elements. To estimate the wavefront disturbances with Shack-Hartmann wavefront sensor we used the 830 nm laser radiation, at the same time the 1550 nm laser beam was used for transferring the optical signal. Measurement of QBER was performed in quantum key distribution system with BB84 protocol
Session 5:
Novel Microdevices II
29 January 2025 • 9:00 AM - 10:25 AM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Vladimir S. Ilchenko, Jet Propulsion Lab. (United States)
13349-18
29 January 2025 • 9:00 AM - 9:20 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
We consider highly localised features of the electromagnetic field, that is, features on the order of a wavelength. Highly localised features are particularly interesting for the computation of plasmonic resonances and the analysis of photonic nanojets. Computing highly localised features of the electromagnetic field is challenging for conventional methods such as FEM because of the need to refine the entire mesh and to use ad hoc numerical solutions to truncate open domains. We define a computational setup and give some theoretical background for the modified Born series approach based on the vectorial Lippmann-Schwinger equation, including a constant overrelaxation parameter, still guaranteeing convergence. We stress that the purpose is to introduce and illustrate a practically computable sufficient method for a constant overrelaxation parameter to make the MBS convergent and not to argue that it is competitive in its present form with the existing methods.
13349-19
29 January 2025 • 9:20 AM - 9:40 AM PST | Moscone South, Room 207 (Level 2)
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The germanium-on-zinc selenide (GOZ) platform is promising for longwave infrared (LWIR) applications due to its low optical losses and high confinement. However, fabrication challenges exist, such as sloped sidewalls from wet etching and increased roughness from dry etching. This work uses metal-assisted chemical etching to achieve smooth, vertical sidewalls, resulting in ultra-low loss GOZ waveguides, micro-resonators, and couplers. This approach suggests GOZ could enable ultra-low loss integrated photonics in the LWIR, similar to silicon-on-insulator platforms in the near-infrared.
13349-20
29 January 2025 • 9:40 AM - 10:00 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Photonic crystal microring (PhCR) devices integrate the photonic crystal concept into whispering gallery mode resonators, leading to better spatial confinement while maintaining high optical quality factors. These devices have been quickly applied in various areas, including optical parametric oscillation, frequency comb generation, vortex light emission, and laser self-injection locking. Despite these broad range of studies, a full understanding of PhCR loss spectra and scattering channels is still unmapped. Current studies focus on mode splitting in the Bragg grating regime and the loss rate of the vortex emission regime only. In this work, we report experimental data, as well as 3D simulations, for a comprehensive spectroscopic understanding. We identify PhCR radiation channels unambiguously, including one broadband loss channel and one/two narrow band loss channels with asymmetric/symmetric claddings. Our work provides a blueprint for using PhCRs in wideband photonics applications.
13349-22
Picometer-precise fabrication of microresonators for advanced photonic circuits using the SNAP platform
(Invited Paper)
29 January 2025 • 10:00 AM - 10:25 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
We report the advancements in the picometer-precise fabrication of microresonators and resonant photonic circuits using the Surface Nanoscale Axial Photonics (SNAP) platform. The requirement for picometer precision in microphotonic devices is critical in applications such as microwave photonic filters, frequency combs, and signal processors. Our research explores several fabrication techniques, including CO2 laser annealing, femtosecond laser inscription, slow cooking, and fiber bending, each demonstrating the capability to achieve the required precision in the nanoscale effective radius variation of microresonators. Additionally, we provide insights into the experimental results of these techniques, highlighting their effectiveness in producing microresonators with high Q-factors and wavelength precision essential for advanced photonic applications. The SNAP platform’s precision in microresonator fabrication represents a significant advancement, paving the way for the development of high-performance photonic devices for optical communications and signal processing.
Break
Coffee Break 10:25 AM - 10:55 AM
Session 6:
Microwave Photonics I
29 January 2025 • 10:55 AM - 12:05 PM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Andrey B. Matsko, Jet Propulsion Lab. (United States)
13349-23
29 January 2025 • 10:55 AM - 11:20 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Whispering-gallery-mode resonators fabricated from magnesium fluoride produce some of the highest finesse microresonator devices, allowing optical frequency combs to be excited with low optical powers. They are typically fabricated using diamond-point turning and polishing, which, unfortunately, often result in a large mode volumes which supports multiple spatial modes. These modes interact, leading to complex dispersion properties. Here, we explore fabrication using ultra-sharp diamond point tools, allowing high resolution resonator structures to be defined, which require little polishing. This allows us to fabricate few-mode resonators which are amenable to dispersion engineering, and produce clean and broadband frequency comb spectra.
13349-24
29 January 2025 • 11:20 AM - 11:45 AM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Microwave signal generation with record-low phase noise is demonstrated using a microcomb. The results use 2-point optical-frequency-division with a frequency-agile dispersive wave as a spectral endpoint. The compact all-solid-state reference cavity features a record Q-factor. Meanwhile, the microcomb is demonstrated to be hybridly-packaged with a III-V DFB pump to perform the 2-point optical-frequency-division, under the turnkey self-injection locking configuration. The results advance integrable microcomb-based signal sources into the performance realm of much larger microwave sources.
13349-25
29 January 2025 • 11:45 AM - 12:05 PM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Optical frequency division based on bulk or fiber optics provides unprecedented spectral purity for microwave oscillators. To extend the applications of this approach, the challenges are to develop miniaturized oscillators without trading off phase noise performance. Here we report a chip-scale high performance photonic microwave oscillator based on integrated electro optical frequency division. Dual DFB lasers are co-self-injection-locked to a single silicon nitride spiral resonator to provide a record high-stability, fully on-chip optical reference. An integrated electro-optical frequency comb based on a thin-film lithium niobate phase modulator chip is leveraged for the first time to perform optical-to-microwave frequency division. The resulting integrated photonic microwave oscillator achieves a record low phase noise for chip-scale oscillators.
Break
Lunch/Exhibition Break 12:05 PM - 1:35 PM
Session 7:
Microwave Photonics II
29 January 2025 • 1:35 PM - 3:30 PM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Andrea M. Armani, The Univ. of Southern California (United States)
13349-26
29 January 2025 • 1:35 PM - 2:00 PM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Electro-optic upconversion in microresonators has been explored for shifting microwave photons (~10 GHz) into the optical domain for linking qubits for communication in a quantum network. There has also been interest in detecting photons at higher frequencies in the terahertz domain (>0.1 THz) particularly for applications in radio astronomy and earth observation. Here, I present the experimental demonstration of multichannel upconversion of signals that are an octave higher than previously demonstrated. The scheme involves the optical signals being resonant in a whispering gallery mode resonator made of lithium niobate. It shows multichannel detection at a photon number efficiency of 2.5E-6 photons per milliWatt of pump power at 0.16 THz. For higher sensitivity, the device can be implemented with the terahertz field being resonant as well.
13349-27
29 January 2025 • 2:00 PM - 2:25 PM PST | Moscone South, Room 207 (Level 2)
Show Abstract +
Multiple microwave photonics platforms have been proposed for transmitting, filtering, channelizing, processing, generating, and detecting radiofrequency and microwave signals. Despite the large bandwidths, low losses, and sensitive detection available with optical carriers, the efficiency of microwave-to-optical conversion via electro-optic modulation remains limited. Consequently, the use of microwave front-ends with high-gain, low-noise amplifier (LNA) stages and associated filters is essential to minimize the system noise figure. This work presents various topologies of microwave circuits embedding resonant electro-optic lithium niobate modulators that function as millimeter and submillimeter-wave receivers with noise figures comparable to state-of-the-art LNAs. We find that these modulators, similar to transistors or any two-port network, have an optimal input impedance that maximizes the signal-to-noise ratio at the output. By co-designing microwave and photonic integrated circuits, we can realize hyperspectral receivers that eliminate the need for LNAs and cover multiple narrow bands in the 100 GHz to 1 THz range.
13349-28
29 January 2025 • 2:25 PM - 2:45 PM PST | Moscone South, Room 207 (Level 2)
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Short millimeter wave band radars require high sensitivity front end and low phase noise local oscillator to improve their resolution and range. We present the results of development of W-band photonic oscillator with phase noise -120dBc/Hz at 10kHz offset based on self-injection-locked microcomb and monolithic high finesse Fabry-Perot cavity, and also W-band photonic front end based on electrooptic resonator with whispering-gallery modes.
13349-29
Low noise micro- and millimeter-wave generation on chip
(Invited Paper)
29 January 2025 • 2:45 PM - 3:10 PM PST | Moscone South, Room 207 (Level 2)
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Recent advances in integrated photonics are enabling for significant improvements in the generation of low-noise micro- and millimeter-wave signals. This talk will provide an overview of cutting-edge approaches integrated lasers, and reference cavities that allow the chip-scale generation of ultralow noise micro- and millimeter-waves. This will include the implementation of optical frequency division (OFD), as well as Pound-Drever-Hall locking on a single chip, which enhances the stability of self-injection locked lasers over long time scales. Addressing the lack of frequency tunability in OFD photonic techniques, we introduce a hybrid opto-electronic approach that combines OFD with direct digital synthesis to produce tunable low-phase-noise microwaves across the X-band. The synthesizer architecture is fully compatible with integrated photonic implementations, paving the way for compact, high-precision and frequency agile microwave sources in chip-scale packages. Together, these advancements represent a significant leap forward in precision frequency control with low size, weight and power integrated photonics for applications in navigation, radar-based sensing and communications.
13349-30
29 January 2025 • 3:10 PM - 3:30 PM PST | Moscone South, Room 207 (Level 2)
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On-chip optical sources are an essential part of fully functional photonic integrated circuits. We show a range of on-chip optical sources from THz to optical frequencies. These include hyperbolic metasurface near-infrared light sources emitting highly linearly polarized light, topologically protected robust single-mode lasers, nanoscale LEDs capable of supporting high-speed on-chip optical communication, and photonic crystal ferromagnet/ultrawide bandgap semiconductor heterostructures spintronic THz emitters. These light sources are all compatible with existing integrated circuit platforms.
Break
Coffee Break 3:30 PM - 4:00 PM
Session 8:
Beam Control
29 January 2025 • 4:00 PM - 5:20 PM PST | Moscone South, Room 207 (Level 2)
Session Chair:
Vladimir S. Ilchenko, Jet Propulsion Lab. (United States)
13349-31
29 January 2025 • 4:00 PM - 4:20 PM PST | Moscone South, Room 207 (Level 2)
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We present a direct experimental demonstration that spatial beam self-cleaning in nonlinear multimode graded-index optical fibers results from the nonequlibrium evolution of the mode population towards a state of thermal equilibrium. This process is shown to be a result of the maximization of the optical entropy of the modal distribution. Entropy maximization is observed both when the input beam power is increased with a fixed length of fiber, as well as when the fiber length grows larger and the input beam power is kept a constant.
13349-32
29 January 2025 • 4:20 PM - 4:40 PM PST | Moscone South, Room 207 (Level 2)
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In this work, we exploit wavefront-sensing based approach for Spatio-spectral characterization of broadband femtosecond pulses.
The measurement was performed the Apollon multi-Petawatt laser system (CEA Saclay, France). The leaked laser beam was collected after the 2-grating compressor and the down collimator. This obtained results demonstrate the suitability of the device for compressor alignment. We will present as well concrete results on other high-power ultrashort laser beamlines, highlighting the interest of wavefront-sensing based approach offering a high resolution on both spectral and spatial phases.
13349-33
29 January 2025 • 4:40 PM - 5:00 PM PST | Moscone South, Room 207 (Level 2)
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We explore and demonstrate an integrated OPA design using complementary grating emitters (CGE). Two grating emitters are utilized: one optimized to emit to the +1-diffraction order and another to the -1 order, which rotated by 180° in the array. Both emitters have similar beam pattern shape and emission efficiency. This method introduces a new degree of freedom to OPA design. The OPA beamsteering is now confined by the averaged element factor; A mismatch of the peak emission angles introduced by design broadens (even doubles) the beamsteering range in elevation direction. Higher degree of mismatch out of the peak region can further suppresses the sidelobes. The 180°-rotated -1-order emitters allow waveguide routing from the opposite direction, which mitigates the density of the waveguides.
13349-34
29 January 2025 • 5:00 PM - 5:20 PM PST | Moscone South, Room 207 (Level 2)
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We present a robust and industrial-grade evaluation of the GLOphotonics BDS-HP-STB long term, an 8-meters long hollow core fiber laser beam delivery system, over continuous long-term periods (14 to 150 hours). Designed to meet the most stringent industrial requirements, it was sequentially tested with the three NIR lasers ranging in power from 40 W to 150 W and pulse duration from 300 fs to continuous-wave. The system demonstrated exceptional performance in power handling and operation condition, with ~0.1% RMS relative output power stability, M2 of less than 1.2, and more than 90% transmission efficiency across all tests. These results affirm that the BDS-HP-STB is not only industry-ready but also also a critical component poised to accelerate the advancement in laser micro-machining, addressing the current innovation gap in thus high-demand field
Conference Co-Chair
Sadovsky Institute of Geosphere Dynamics (Russian Federation)
Program Committee
Institute for Research in Electronics & Applied Physics (United States), Univ. of Maryland, College Park (United States)
Program Committee
Harvard John A. Paulson School of Engineering and Applied Sciences (United States)
Program Committee
Nicolás Quesada
Polytechnique Montréal (Canada)
Program Committee
Okinawa Institute of Science and Technology Graduate Univ. (Japan)
Additional Information
POST-DEADLINE SUBMISSIONS SITE CLOSED 2-December
We are in the process of placing new submissions and the contact author will be notified of acceptance by 16-December
We are in the process of placing new submissions and the contact author will be notified of acceptance by 16-December
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