The potential of magnons in shaping the future of quantum computing and information technology is truly remarkable. Of particular note is the coherent state of magnons, which emerges from their Bose-Einstein condensation (mBEC). Typically, the formation of mBEC occurs within the magnon excitation zone. Using optical methods, we demonstrate for the first time, the persistent existence of mBEC at considerable distances from the source of magnon excitations. The mBEC phase exhibits a demonstrable degree of homogeneity. Yttrium iron garnet films, magnetized perpendicular to the plane of the film, were used for experiments conducted at room temperature. For the development of coherent magnonics and quantum logic devices, we adopt the method explained in this article.
Vibrational spectroscopy provides valuable insights into chemical specification. Sum frequency generation (SFG) and difference frequency generation (DFG) spectra show a delay-dependent variance in the spectral band frequencies corresponding to the same molecular vibration. PF-04957325 mouse A numerical investigation of time-resolved SFG and DFG spectra, incorporating a frequency reference within the incident infrared pulse, pinpointed the source of the frequency ambiguity as residing in the dispersion of the initiating visible pulse, rather than in any surface structural or dynamic modifications. Employing our findings, a beneficial approach for correcting discrepancies in vibrational frequencies is presented, thus improving the accuracy of spectral assignments for SFG and DFG spectroscopies.
This systematic investigation explores the resonant radiation emitted by localized soliton-like wave-packets supporting second-harmonic generation in the cascading regime. PF-04957325 mouse A comprehensive mechanism is presented for the growth of resonant radiation, independent of higher-order dispersion, primarily through the action of the second-harmonic component, accompanied by the emission of radiation around the fundamental frequency via parametric down-conversion. The encompassing presence of this mechanism is highlighted through examination of different localized waves, including bright solitons (both fundamental and second-order), Akhmediev breathers, and dark solitons. To account for the frequencies emitted by such solitons, a straightforward phase-matching condition is proposed, correlating well with numerical simulations conducted under alterations in material parameters (e.g., phase mismatch, dispersion ratio). The mechanism of soliton radiation within quadratic nonlinear media is unambiguously elucidated by the provided results.
A contrasting configuration, featuring one biased and one unbiased VCSEL, situated opposite one another, signifies a potential advancement over the conventional SESAM mode-locked VECSEL approach in generating mode-locked pulses. Numerical analysis of a theoretical model using time-delay differential rate equations shows that the proposed dual-laser configuration operates as a typical gain-absorber system. Nonlinear dynamics and pulsed solutions display general trends within the parameter space defined by laser facet reflectivities and current.
A novel reconfigurable ultra-broadband mode converter, utilizing a two-mode fiber and a pressure-loaded phase-shifted long-period alloyed waveguide grating, is described. The fabrication of long-period alloyed waveguide gratings (LPAWGs), composed of SU-8, chromium, and titanium, is achieved through the combined application of photolithography and electron beam evaporation. The LPAWG's pressure-dependent application or release on the TMF enables the device to change between LP01 and LP11 modes, showcasing its insensitivity to polarization. Operation within the wavelength range of 15019 nanometers to 16067 nanometers, spanning about 105 nanometers, results in mode conversion efficiencies exceeding 10 decibels. Further utilization of the proposed device encompasses large bandwidth mode division multiplexing (MDM) transmission and optical fiber sensing systems, especially those employing few-mode fibers.
A dispersion-tunable chirped fiber Bragg grating (CFBG)-based photonic time-stretched analog-to-digital converter (PTS-ADC) is proposed, demonstrating a cost-effective ADC system with seven distinct stretch factors. Adaptable stretch factors are obtainable by changing the dispersion of CFBG, thereby permitting the acquisition of varying sampling points. In this way, the system's total sampling rate can be refined. The effect of multi-channel sampling can be realized by increasing the sampling rate via a single channel. Seven sets of stretch factors, encompassing values between 1882 and 2206, were eventually obtained, each set representing a unique sampling point cluster. PF-04957325 mouse Frequencies of input RF signals, ranging from 2 GHz up to 10 GHz, were successfully recovered. Simultaneously, the sampling points are multiplied by 144, and the equivalent sampling rate is correspondingly elevated to 288 GSa/s. The proposed scheme is perfectly suited for commercial microwave radar systems, which enjoy the substantial advantage of a much higher sampling rate at a low price.
Significant progress in ultrafast, high-modulation photonic materials has resulted in a plethora of novel research directions. Consider the exciting prospect of photonic time crystals, a prime illustration. This analysis emphasizes the most recent, promising material breakthroughs, potentially applicable to photonic time crystals. Their modulation's worth is evaluated by analyzing the speed of change and the degree of modulation. Our investigation extends to the hurdles that are yet to be cleared, and includes our estimations of likely paths to accomplishment.
Multipartite Einstein-Podolsky-Rosen (EPR) steering plays a vital role as a key resource within quantum networks. Despite the demonstration of EPR steering in physically separated ultracold atomic systems, deterministic manipulation of steering across distant nodes within a quantum network is essential for a secure communication system. A workable scheme is proposed for the deterministic generation, storage, and manipulation of one-way EPR steering between separate atomic systems using a cavity-enhanced quantum memory approach. By faithfully storing three spatially separated entangled optical modes, three atomic cells achieve a strong Greenberger-Horne-Zeilinger state within the framework of electromagnetically induced transparency where optical cavities successfully quell the inherent electromagnetic noise. By leveraging the substantial quantum correlation within atomic cells, one-to-two node EPR steering is realized, and this stored EPR steering can be preserved in the quantum nodes. Furthermore, the atomic cell's temperature actively alters the system's steerability. This scheme directly guides the experimental implementation of one-way multipartite steerable states, facilitating the design of an asymmetric quantum network protocol.
Within a ring cavity, the quantum phases of a Bose-Einstein condensate and its associated optomechanical responses were meticulously studied. A semi-quantized spin-orbit coupling (SOC) is induced in the atoms due to their interaction with the running wave mode of the cavity field. The observed evolution of the matter field's magnetic excitations closely matches the trajectory of an optomechanical oscillator in a viscous optical medium, characterized by high integrability and traceability independent of atomic interactions. Importantly, the interaction between light atoms causes a sign-flipping long-range interatomic force, dramatically reshaping the system's regular energy profile. A new quantum phase, featuring a high quantum degeneracy, was found in the transitional region of the system with SOC. The scheme's immediate realizability is demonstrably measurable through experiments.
We introduce a novel interferometric fiber optic parametric amplifier (FOPA), a groundbreaking design in our experience, capable of suppressing undesirable four-wave mixing products. We use two simulation models, one focusing on eliminating idler signals, and another specifically targeting non-linear crosstalk rejection from the signal's output port. This numerical analysis demonstrates the practical feasibility of suppressing idlers by greater than 28 decibels across at least ten terahertz. This enables the reuse of idler frequencies for signal amplification and correspondingly doubles the usable FOPA gain bandwidth. The accomplishment of this goal, even with real-world couplers in the interferometer, is illustrated by the addition of a small amount of attenuation in one arm of the interferometer.
Control of far-field energy distribution is demonstrated using a femtosecond digital laser employing 61 tiled channels in a coherent beam. Channels are each treated as individual pixels, allowing independent adjustments of both amplitude and phase. Introducing a phase discrepancy between neighboring fiber strands or fiber layouts leads to enhanced responsiveness in the distribution of far-field energy. This facilitates deeper research into the effects of phase patterns, thereby potentially boosting the efficiency of tiled-aperture CBC lasers and fine-tuning the far field in a customized way.
Optical parametric chirped-pulse amplification generates two broad-band pulses, a signal and an idler, which individually achieve peak powers in excess of 100 gigawatts. Typically, the signal is employed, though compressing the longer-wavelength idler presents novel opportunities for experimentation, where the driving laser's wavelength is a critical variable. Several subsystems were incorporated into the petawatt-class, Multi-Terawatt optical parametric amplifier line (MTW-OPAL) at the Laboratory for Laser Energetics to effectively manage the challenges arising from the idler, angular dispersion, and spectral phase reversal. Within the scope of our knowledge, this constitutes the first achievement of simultaneous compensation for angular dispersion and phase reversal within a single system, generating a 100 GW, 120-fs pulse duration at 1170 nm.
A key determinant in the progress of smart fabrics is the function of electrodes. Common fabric flexible electrodes' preparation often suffers from the drawbacks of expensive materials, intricate preparation methods, and complex patterning, thereby impeding the wider adoption of fabric-based metal electrodes.