Experimental results demonstrate a 38-fs chirped-pulse amplified (CPA) Tisapphire laser system, based on the power-scalable thin-disk design, achieving an average output power of 145 W at a 1 kHz repetition rate, thus corresponding to a peak power of 38 GW. A beam profile characterized by near-diffraction-limit performance and an approximately 11 M2 value was obtained. An ultra-intense laser, boasting superior beam quality, showcases potential surpassing that of a conventional bulk gain amplifier. Based on our current knowledge, this thin-disk Tisapphire regenerative amplifier is the first to report operation at 1 kHz.
An innovative light field (LF) image rendering technique with a controllable lighting mechanism has been devised and empirically verified. The inability of prior image-based methods to render and edit lighting effects for LF images is resolved by this approach. In contrast to prior methods, light cones and normal maps are formulated and utilized to expand RGBD images into RGBDN representations, allowing for a greater range of options in light field image generation. RGBDN data is acquired using conjugate cameras, which simultaneously resolve the issue of pseudoscopic imaging. Employing perspective coherence in RGBDN-based light field rendering leads to a notable speed improvement, achieving an average performance gain of 30 times in comparison to conventional per-viewpoint rendering methods. A self-made large-format (LF) display system has been successfully used to reconstruct three-dimensional (3D) images with vivid realism, including both Lambertian and non-Lambertian reflections, showcasing specular and compound lighting effects in a 3D space. The rendering of LF images gains added flexibility with the proposed method, applicable also to holographic displays, augmented reality, virtual reality, and other related fields.
Fabricated, to the best of our understanding, using standard near-ultraviolet lithography, is a novel broad-area distributed feedback laser featuring high-order surface curved gratings. The simultaneous achievement of increased output power and selectable modes is realized through the application of a broad-area ridge and an unstable cavity structure made of curved gratings and a high-reflectivity coated rear facet. The suppression of high-order lateral modes is achieved by configuring current injection and non-injection regions within an asymmetric waveguide structure. A spectral width of 0.138nm and a maximum output power of 915mW, free from kinks, characterized the 1070nm DFB laser. The device's threshold current is 370mA, and its side-mode suppression ratio, 33dB, is another key feature. The stable performance and straightforward manufacturing process position this high-powered laser for widespread use in applications such as light detection and ranging, laser pumping, optical disc access, and more.
A pulsed, tunable quantum cascade laser (QCL), operating within the significant 54-102 m range, is investigated for synchronous upconversion, using a 30 kHz, Q-switched, 1064 nm laser. The QCL's capacity for precise control over repetition rate and pulse duration facilitates remarkable temporal overlap with the Q-switched laser, resulting in a 16% upconversion quantum efficiency in a 10 mm length of AgGaS2 crystal. In our examination of the upconversion process, we evaluate the noise levels through the lens of pulse-to-pulse energy steadiness and timing variability. In the QCL pulse range of 30 to 70 nanoseconds, the upconverted pulse-to-pulse stability exhibits a value of approximately 175%. selleck The system's impressive combination of broad tunability and high signal-to-noise ratio is ideally suited for mid-infrared spectral analysis of very absorbing samples.
In the study of both physiology and pathology, wall shear stress (WSS) is a crucial factor. Current measurement technologies are deficient in terms of spatial resolution, or lack the ability to quantify instantaneous values without the use of labels. selected prebiotic library Dual-wavelength third-harmonic generation (THG) line-scanning imaging, for immediate wall shear rate and WSS measurement in living subjects, is demonstrated here. The soliton self-frequency shift was instrumental in our generation of dual-wavelength femtosecond laser pulses. For instantaneous determination of wall shear rate and WSS, dual-wavelength THG line-scanning signals are simultaneously obtained, extracting blood flow velocities at adjacent radial positions. The oscillating characteristics of WSS in brain venules and arterioles are evident in our label-free micron-resolution data.
This letter introduces approaches for improving the performance of quantum batteries, and a novel, to the best of our knowledge, quantum power source for a quantum battery operating without the use of an external driving field. Quantum battery performance is found to be significantly augmented by the memory effects of the non-Markovian reservoir, an effect traceable to ergotropy backflow within non-Markovian regimes, a phenomenon absent in the Markovian limit. An enhancement of the peak for maximum average storing power within the non-Markovian regime is achievable via manipulation of the coupling strength between the battery and charger. Ultimately, the battery's charging capability extends to non-rotational wave phenomena, independent of external driving fields.
Tremendous advancements in output parameters of ytterbium- and erbium-based ultrafast fiber oscillators, operating in the spectral regions around 1 micrometer and 15 micrometers, have been achieved by Mamyshev oscillators in recent years. BIOCERAMIC resonance This Letter describes an experimental investigation of generating high-energy pulses within a thulium-doped fiber Mamyshev oscillator, an approach designed to improve performance over the 2-meter spectral range. Employing a tailored redshifted gain spectrum in a highly doped double-clad fiber, highly energetic pulses are generated. Pulses with an energy maximum of 15 nanojoules are emitted from the oscillator; these can be compressed to a duration of 140 femtoseconds.
Chromatic dispersion poses a significant hurdle to the performance of optical intensity modulation direct detection (IM/DD) transmission systems, particularly when dealing with a double-sideband (DSB) signal. To reduce complexity in maximum likelihood sequence estimation (MLSE) for DSB C-band IM/DD transmission, we introduce a look-up table (LUT) based on pre-decision-assisted trellis compression and a path-decision-assisted Viterbi algorithm. Reducing both the LUT size and the training sequence's duration was facilitated by our proposed hybrid channel model, a combination of finite impulse response (FIR) filters and look-up tables (LUTs) for the LUT-MLSE decoder. For PAM-6 and PAM-4, the suggested techniques enable a compression of the lookup table (LUT) size to 1/6th and 1/4th, respectively, leading to a 981% and 866% reduction in the number of multipliers required, with a marginal decrement in performance. Our successful demonstration encompassed a 20-km 100-Gb/s PAM-6 and a 30-km 80-Gb/s PAM-4 C-band transmission across dispersion-uncompensated links.
A general method is presented for the redefinition of permittivity and permeability tensors within a medium or structure with spatial dispersion (SD). The method effectively addresses the entanglement of electric and magnetic contributions within the traditional framework of the SD-dependent permittivity tensor, isolating each component. For accurate modeling of experiments encompassing SD, the common methods for calculating the optical response of layered structures depend on the redefined material tensors.
We present a compact hybrid lithium niobate microring laser, a device built by directly connecting a commercial 980-nm pump laser diode chip to a high-quality Er3+-doped lithium niobate microring chip. Lasing emission at a wavelength of 1531 nanometers, originating from an Er3+-doped lithium niobate microring, is demonstrably achievable through 980-nm laser pumping. A lithium niobate microring laser, compact and hybrid, is nestled within a 3mm x 4mm x 0.5mm chip. At atmospheric temperature, the laser's threshold pumping power is 6mW, and its corresponding threshold current is 0.5A (operating voltage 164V). A spectrum displaying single-mode lasing with a very narrow linewidth, just 0.005nm, was observed. This work focuses on the potential applications of a robust hybrid lithium niobate microring laser source, particularly within coherent optical communication and precision metrology.
We present an interferometric frequency-resolved optical gating (FROG) approach to expand the detection range of time-domain spectroscopy into the demanding visible light frequencies. Our numerical simulations show a double-pulse operation activating a unique phase-locking mechanism that preserves both zero- and first-order phases. These phases are critical for phase-sensitive spectroscopy, and are unavailable using standard FROG measurements. Our time-domain signal reconstruction and analysis protocol highlights the enabling and suitable nature of time-domain spectroscopy with sub-cycle temporal resolution for an ultrafast-compatible and ambiguity-free method of determining complex dielectric functions at visible wavelengths.
The 229mTh nuclear clock transition's laser spectroscopy is a prerequisite for future nuclear-based optical clock construction. For this endeavor, broad-spectrum vacuum ultraviolet laser sources are required. We report on a tunable vacuum-ultraviolet frequency comb, a result of cavity-enhanced seventh-harmonic generation. The 229mTh nuclear clock transition's current uncertainty range is encompassed by its tunable spectral range.
Our proposed spiking neural network (SNN) architecture, detailed in this letter, utilizes cascaded frequency and intensity-modulated vertical-cavity surface-emitting lasers (VCSELs) for optical delay-weighting. The plasticity of synaptic delays within frequency-switched VCSELs is meticulously researched by means of numerical analysis and simulations. The principal factors behind the manipulation of delay are investigated, leveraging a tunable spiking delay extending up to 60 nanoseconds.