The performances of two liquid level sensors based on long-period fiber gratings are studied. The long-period gratings (LPGs) have similar characteristics (length and period), but are fabricated with two photosensitive B-Ge co-dop

We describe a novel performance optimization method for all-optical amplitude reshaping via degenerated four-wave mixing (FWM) in highly nonlinear optical fiber. The proposed optimization method is achieved by judiciously configur

We present a network-level signaling mechanism for user access and service setup in light emitting diode (LED)-based visible light communication (VLC) networks and define the corresponding signaling messages. In this mechanism, la

A simple fiber tip sensor for refractive index (RI) measurement based on Fabry–Perot (FP) interference modulated by Fresnel reflection is proposed and demonstrated. The sensor head consists of an etching-induced micro air gap near

A pulsed master oscillator power amplifier system is constructed using a double-cladding polarized Yb-doped fiber and an all-fiber Q-switched narrow-linewidth pulsed laser used as seed laser. This system has a high repetition rate

A two-dimensional (2D) distributed feedback (DFB) structure is fabricated on dye-doped sol-gel derived hybrid zirconia films by soft lithography. The Q-switched Nd:YAG laser (\lambda = 532 nm) is used to pump these structures. The

The circular-like sidewall and trench around the periphery of the crater are obtained on Zinc metal surface subjected to fewer than 200 cumulative pulses laser ablation. These patterns can be attributed to the higher secondary hea

We demonstrate a 30-W all-fiberized laser in a master oscillator power amplifier (MOPA) structure with a central wavelength of 1 950 nm. The laser is a continuous-wave (CW) operation with double-clad Tm-doped silica fiber pumped b

Lock-in phenomenon in ring laser gyroscopes is directly related to effective backscattering, which includes both backscattering and nonuniform loss. Effective backscattering often differs in different states and can only be reflec

We employ plane-wave with ultrasoft pseudopotential method to calculate and compare the total density of states and partial density of states of bulk-phase GaN, Ga0:9375N, and GaN0:9375 systems based on the first-principle density

The fluorescence power from biological tissue excited by a femtosecond laser pulse compared with excitation power does not appear to obey a simple quadratic relationship given by the steady non-linear theory. A more reliable analy

We present a theoretical calculation of the dependence of reflectivity Rpp of the improved fully leaky waveguide geometry, which comprises pyramid, matching fluid, and strongly anchored hybrid-aligned nematic liquid crystal (NLC)

The polarization state is modulated by tilting birefringence component placed in the feedback external cavity. The variation of the polarization state in one period of modulation is found to be similar to sine wave. The periods be

We show that absorbed and stored electromagnetic energy are proportional to the reflection group delay in highly reflective dispersive dielectric mirrors over the high-reflectivity band. Our theoretical considerations are verified

We present an experimental and theoretical study of self-rotation of optical polarization in a rubidium vapor. The atomic vapor is placed in a magnetic shielding cavity to suppress the Faraday rotation effect. In our experiment, D

We present a design for tunable directional beaming through a subwavelength metallic double slit surrounded by dielectric surface-relief gratings. On-axis and off-axis beaming can be switched by controlling the incident angle to a

Chaotic laser radar based on correlation detection is a high-resolution measurement tool for remotely monitoring targets or objects. However, its effective range is often limited by the side-lobe noise of correlation trace, which

An approach to the simultaneous measurement of refractive-index (RI) and temperature changes using optical ring resonators is proposed and theoretically demonstrated. With a liquid-core silica ring resonator as an example, two dif

A practicable experimental method for measuring scattering on rough surfaces is reported. The scattered patterns are captured on a screen composed of two pieces of ground glass and then imaged using a charge-coupled device. The sc

This letter proposes and experimentally demonstrates a simple scheme for generating 40-GBaud carrier-suppressed return-to-zero differential quadrature phase shift keying (CSRZ-DQPSK) modulation signals with tunable pulsewidths usi

A three-wavelength lidar system is set up. The backscatter signals of 355, 532, and 1 064 nm are measured simultaneously to derive the optical depth, lidar ratio, and backscatter color ratio of cirrus clouds, respectively. The lid

Chemical warfare agents (CWAs) are recognized as serious threats of terrorist acts against the civilian population. Minimizing the impact of these threats requires early detection of the presence of CWAs. Cavity ring-down spectros