Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2610.23549

A compact, dual-colour chirped-pulse laser system for field-deployable coherent Rayleigh-Brillouin scattering diagnostics

Yingjie Zhao·Gabriel M. Flores Alfaro·Carmen Pascual-Fort·Gabi-Daniel Stancu·Alexandros Gerakis
View original source ↗Read source document ↗Export metadata ↓

Abstract

Single-shot coherent Rayleigh-Brillouin scattering (CRBS) requires dual colour, frequency, and pulse duration agile laser systems, currently available only in laboratory layouts. In this work, we present a compact, portable, and robust next generation laser system that meets all of these requirements. Key features include an integrated master-slave seed laser design for stable frequency chirping, fiber-coupled acousto-optic modulator (AOM) gated pulse shaping for long-term thermal stability, and customized amplification stages in a rugged, portable enclosure which simplifiy the alignment and maintenance process. The system in this implementation can deliver up to $450$~mJ per arm, chirp rates up to $\sim22$~MHz$/$ns, and arbitrary temporal profiles within $\sim25$~ns to $\sim1$~$μ$s. This laser system is validated by measuring the neutral number density of an atmospheric plasma jet, and a two-dimensional temperature map is constructed, demonstrating lab-grade diagnostics for field deployment.

Explore related subjects

physics.optics

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Yingjie Zhao, Gabriel M. Flores Alfaro, Carmen Pascual-Fort, Gabi-Daniel Stancu, Alexandros Gerakis. 2026-10-16. A compact, dual-colour chirped-pulse laser system for field-deployable coherent Rayleigh-Brillouin scattering diagnostics. https://arxiv.org/abs/2610.23549

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

All-optical Lithography for Spatiotemporal Patterning of High-Modulation Azopolymer Microreliefs

Microstructured surfaces are central to photonics, biointerfaces, and coating technologies, but they are typically fabricated through multistep workflows involving masks, masters,development, and etching. Azopolymers offer a direct light-driven route to surface structuring, although holographic photopatterning of flat films has largely remained limited to smooth, shallow, and engraving-like reliefs with limited vertical modulation. Here we show that computer-generated holograms with co-designed bright and dark regions can spatially confine inward mass transport and directly generate isolated protruding microstructures with surface modulations of several micrometers from pristine flat azopolymer films. Single exposures produce individual protrusions and arrays, whereas sequential tailored exposures generate flattopped and hierarchical microreliefs. The same workflow produces connected freeform structures and enables optical erasure and rewriting within the same surface region. We further transfer the optically programmed azopolymer morphologies into another transparent polymer and demonstrate replicated microlenses operating at multiple visible wavelengths, with focal response controlled through the master-writing parameters. These results establish an alloptical framework for generating and reconfiguring complex, high-modulation azopolymer microreliefs from flat films through combined control of holographic illumination geometry and exposure history, with replication extending their use to materials selected for their final functional properties.

physics.optics↗
arXiv2026

Dirac branch-cut modes with relativistic transport

Emergent Dirac fields, exhibiting effective relativistic physics, are most commonly associated with bulk and surface states in materials such as graphene and topological insulators. Here we show that phase dislocations of a complex Dirac mass support a distinct family of propagating Dirac defect states that behave as massless or massive one-dimensional relativistic modes. These traveling-wave defect states, termed Dirac branch-cut (DBC) modes, are governed by a one-dimensional Dirac Hamiltonian whose effective mass is controlled by the phase difference across the branch cut. Using acoustic metamaterials, we experimentally demonstrate a range of relativistic phenomena exhibited by DBC modes, including relativistic dispersion, energy-independent confinement, Klein tunnelling, and transport along freeform (e.g., spiral) trajectories. Our results establish branch-cut defects as a distinct platform for realizing propagating Dirac defect states, extending relativistic Dirac physics from bulk and surface states to propagating modes confined to defect boundaries.

physics.optics↗
arXiv2026

Offset Dual Microcombs in a Single Microresonator: Kerr-Raman Interleaved Combs

Integrated Kerr microcombs have emerged as a central platform for chip-scale nonlinear photonics. One of their most compelling applications is dual-comb technology, which enables fast, high-resolution, coherent optical spectroscopy, precision metrology, ranging, and ultrasensitive sensing by interfering two frequency combs with slightly different repetition rates. However, no effective strategy yet exists to synergistically excite multiple spatial mode families, manage mode competition and energy partitioning, and precisely engineer dispersion, leaving offset co-propagating dual-microcombs in a single resonator elusive. Here we demonstrate a new mechanism for offset dual microcombs formation via Kerr-Raman interleaving for the first time, by leveraging single Raman-active thin-film lithium niobate microrings. Two spatial mode families with high loaded Q factors up to 5 million are dispersion engineered to have nearly identical free-spectral-ranges but a designed relative frequency offset. Stimulated Raman scattering efficiently generates a Raman comb in one family alongside a Kerr comb in the other. The two combs interleave with a fractional offset to form a broadband, densely interleaved spectrum. Pumping the microring at only 320 mW yields Kerr-Raman interleaved dual combs both featuring nearly identical repetition rates around 102 GHz with a small difference of 675 MHz, a relatively flat envelope exceeding 29 nm and an intrinsic comb-line linewidth of 410 Hz. Our results establish offset dual-comb generation in a single microresonator, enabling compact dual-comb sources for chip-scale precision spectroscopy, Vernier-enhanced sensing, and advanced quantum photonics.

physics.optics↗