The 2024 moment magnitude 7.5 Noto Peninsula (Japan) earthquake caused devastation to communities and was generated by a complex rupture process. Using space geodetic seismic observations, we have shown that the event deformed peninsula with peak uplift reaching 5 meters at west coast. Shallow slip exceeded 10 on an offshore fault. Peak stress drop greater than megapascals. This devastating began slow propagation lasting 15 20 seconds near its hypocenter, where swarms had surged since 2020...

The turning point of the refractive index (RI) sensitivity based on multimode microfiber (MMMF) in-line Mach–Zehnder interferometer (MZI) is observed. By tracking resonant wavelength shift MZI generated between HE11 and HE12 modes in MMMF, surrounding RI (SRI) could be detected. Theoretical analysis demonstrates that will reach ±∞ either side due to group effective difference (G) approaching zero. Significantly, positive exists a very wide fiber diameter range, while negative can achieved...

A multimode microfiber (MMMF)-based dual Mach-Zehnder interferometer (MZI) is proposed and demonstrated for simultaneous measurement of refractive index (RI) temperature. By inserting a section MMMF supporting few modes in the sensing arm MZI setup, an inline interference between fundamental mode high-order MMMF, as well reference arm, i.e., MZI, realized. Due to different mechanisms, former achieves RI sensitivity 2576.584 nm/RIU temperature -0.193 nm/°C, while latter one 1001.864 0.239...

A compact and low cost fiber sensor based on single multimode microfiber with Fresnel reflection is proposed demonstrated for simultaneous measurement of refractive index temperature. The fabricated two simple steps including tapering then endface cleaving. spectrum an intensity modulated interference spectrum, as the tapered generates pattern cleaved provides modulation. By demodulating fringe power free range (FSR) RI sensitivities -72.247dB/RIU 68.122nm/RIU, well temperature 0.0283dB/°C...

An approach to realizing simultaneous measurement of refractive index (RI) and temperature based on a microfiber-based dual inline Mach-Zehnder interferometer (MZI) is proposed demonstrated. Due different interference mechanisms, as one between the core mode lower order cladding in sensing single-mode fiber other fundamental high-order multimode microfiber, former achieves RI sensitivity -23.67 nm/RIU 81.2 pm/°C, whereas those latter are 3820.23 nm/RIU, -465.7 respectively. The large...

The dense blue-green wavelength division multiplexing (WDM) technology has been rarely reported to increase the capacity of optical communications, since there are no available multi/demultiplexers with nanometer-scale spacing for light. In this work, a polarization-sensitive phased array (OPA) is proposed effectively separate wavelengths fine by innovative mode multiplexing. efficient OPA based on fishbone waveguide antenna demonstrated successfully demultiplex in WDM wireless communication...

The episodic stick-slip behavior of megathrust faults in subduction zones can lead to severe earthquakes and tsunamis that pose a catastrophic threat coastal populations. It is therefore great importance study their seismogenic conditions earthquake activity. Sumatra Java, located seaward the Sunda Arc, are geographically neighboring, but phenomena differ significantly. zone has been scene numerous very strong (Mw > 8), including 2004 magnitude Mw 9.1, while Java experienced only limited...

Postseismic deformation following large earthquakes provides critical insights to the stress state and rheology of seismogenic zones. Here, we use high-resolution geodetic observations analyze postseismic response 2024 moment magnitude (Mw) 7.5 Noto earthquake, highlighting complex interactions between coseismic slip afterslip on subparallel faults. By examining approximately six months using InSAR GNSS data, observe dramatic subsidence exceeding 8 cm across Peninsula, alongside horizontal...

Postseismic deformation in the far field following large earthquakes is increasingly recognised as a key factor contributing to regional land height and relative sea-level (RSL) changes. The Sumatran subduction zone provides unique setting study this owing availability of far-field (600 – 1000 km from trench) long-term (>20 years) Global Navigation Satellite System (GNSS) observations. In study, we model GNSS-constrained postseismic multiple great (Mw ≥ 8.0) using...

We observe high optical quality factor (Q) polygonal and star coherent modes in a lithium niobate microdisk. In contrast to the previous polygon achieved by deformed microcavities at lower mechanical Q, we adopted weak perturbation from tapered fiber for mode formation. The resulting intracavity power of triggers second harmonic generation efficiency. With combined advantage Q cavity optomechanical oscillation was observed first time. Finally, frequency microcomb with an ultra stable...

The linear polarized (LP) mode multiplexer based on the inverse designed multi-plane light conversion (MPLC) has advantages of low insertion loss and crosstalk. However, also requires fabrication alignment accuracy in experiments, which have not been systematically analyzed. Here, we perform error tolerance analysis MPLC summarize design rules for LP multiplexer/demultiplexer. tolerances process experimental demonstration are greatly released with proper parameters input/output optical beam...

Abstract Following great subduction earthquakes, postseismic deformation of coastal areas shows consistent seaward motion but complex vertical deformation. Understanding both the horizontal and components in same geodynamic framework presents challenges. Here, by modeling short‐term (a few years) viscoelastic relaxation (VER) afterslip following synthetic real we demonstrate that complexity can be explained simple terms. Along a margin‐normal profile, VER results an up‐down‐up trisegment,...

Three-dimensional surface displacement field associated with the 25 April 2015 Gorkha, Nepal earthquake is derived from an integration of Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) measurements, extended SISTEM (Simultaneous Integrated Strain Tensor Estimation From Geodetic Satellite Deformation Measurements) approach (ESISTEM) proposed in this study. In ESISTEM approach, both surrounding InSAR GPS measurements can be used as constraints deriving...

Abstract The geographic coincidence of the Chile Ridge slab window and Patagonia ice fields offers a unique opportunity for assessing effects rheology on glacial isostatic adjustment (GIA). Mass loss these since Little Ice Age causes rapid but variable crustal uplift, 12–24 mm/yr around North field, increasing to maximum 41 South as determined from newly collected or processed geodetic data. We used observational constraints in three-dimensional Maxwell viscoelastic finite element model GIA...

We report the study of lasing modes in broad-area, equilateral-triangular laser cavities. An alternative approach is proposed to optical equilateral triangular cavities an analytical form. The were obtained by examining simplest paths inside cavity, which yields final solution with boundary conditions. can be fabricated from semiconductor heterostructures grown on (111)-oriented substrates, easily cleaved into shapes. Such a design takes advantage total internal reflection at facets cavity...

We demonstrate efficient tuning of a monolithically integrated lithium niobate (LN) microdisk optical frequency microcomb. Utilizing the high quality (Q) factor (i.e., Q∼7.1×106) microdisk, microcomb spans over spectral bandwidth ∼200nm at pump power as low 20.4 mW. Combining large electro-optic coefficient LN and optimum design geometry microelectrodes, we electro-optical comb with range 400 pm efficiency ∼38pm/100V.

Seismic hazard evaluation at critical infrastructures, such as nuclear power plant, urges deeper understanding on the fundamental physics that govern initiation, propagation and termination of damaging earthquakes. The 2024 moment magnitude (Mw) 7.5 Noto Peninsula earthquake produced great hazards exhibited complex rupture process. We derive high-resolution 3D surface deformation event using dense space geodetic observations, which reveal two major zones separated by ~40 km along coast...

We present a new method to derive 3-D surface deformation from an integration of interferometric synthetic aperture radar (InSAR) images and Global Navigation Satellite System (GNSS) observations based on Akaike's Bayesian Information Criterion (ABIC), considering relationship between deformations neighbouring locations. This avoids interpolated errors by excluding the interpolation GNSS into same spatial resolution as InSAR harnesses data sets prior smooth constraints objectively...

Abstract Subduction megathrust ruptures that breach the trench, such as in 2011 M = 9 Tohoku‐oki earthquake, can be very tsunamigenic. However, whether buried are intrinsically less tsunamigenic has not been fully investigated. Here, we conduct this investigation by studying mechanics of seafloor deformation and resultant tsunami runup. With a trench‐breaching rupture, is dominated rigid‐body translation frontal upper plate, uplift enhanced horizontal motion sloping seafloor. reduced, but...

A high sensitive temperature sensor based on D-shaped microfiber with birefringence is proposed and demonstrated. In order to obtain microfiber, we polish a single mode fiber (SMF) then taper down the polished region into micrometer size. By utilizing Sagnac loop interferometer, achieve refractive index (RI) sensitivity of 9951nm/RIU. Further, realize detection assisted by sucrose solution thermo-optic coefficient. Experimental results demonstrate up -0.98921nm/°C within range 22°C-60°C. The...

An iterative method for the computation of 2-D quasi-grammians is developed, where each iteration involves solving two 1-D Lyapunov equations. For a stable system, algorithm converges to desired solutions very quickly. Further, an based on unconstrained optimization developed structured grammians. The steps. first step minimize norm system matrix by similarity transformations; second use scaling technique accomplish optimization. Two examples are given evaluate performance reduced-order...