Effect Of Pump Wavelength Research Articles

Ultra sub-wavelength resolution terahertz near-field imaging: modelling via the FDTD method in a multi-pixel sampling approach

In this work, the finite difference time domain (FDTD) method is used to optimize the multi-pixel sampling approach, in order to achieve ultra-high spatial resolution (∼ λ/110) in the near-field region. The optimization is performed based on the optical pump pulse wavelength, the thickness of the silicon modulator, and the size of the aperture in the projected pattern. To the best of our knowledge, this is the first time that the FDTD method has been used to improve near-field resolution. In addition, we consider the effect of pump wavelength on near field imaging resolution for the first time.

Effect of pump wavelength and temperature on the spectral performance of BAC-Al in bismuth-doped aluminosilicate fibers.

The near-infrared luminescence of Bi-doped aluminosilicate fiber within pump wavelengths between 710 and 990nm and under varying pump powers and operation temperatures has been investigated systematically. It is revealed that there exist two emission bands peaking around 1120 and at 1300nm, which are believed to be associated with two different aluminum-related bismuth active centers (BAC-Al1 and BAC-Al2); the BAC-Al2 is found to be more efficiently excited at a lower temperature within the spectral range of 790-850nm. This is the first time, to the best of our knowledge, that two sub-bands of BAC-Al are identified. The thermal annealing effect on the luminescence of BACs is also studied under 830nm pumping. In contrast to the quenching of BAC-Si, the luminescence intensity of BAC-Al1 is enhanced by 1.5 times after 500°C heating and subsequent cooling. The results demonstrate an effective strategy for tuning the emission scheme in the range of 1100-1400nm by adjusting the excitation wavelength and operation temperature.

Broadband mid-infrared supercontinuum generation in novel [formula omitted] step-index fibers

We experimentally demonstrate the mid-infrared supercontinuum generation in a chalcogenide step-index fiber consisting of an As2Se3 core and an As2Se2S cladding. The fiber with the core diameter of 21μm was fabricated through the rod-in-tube technique and fiber-drawing process. The effect of pump wavelength, fiber length, and pump power on the spectral bandwidth and output power of the supercontinuum spectra generated from the fiber pumped by the ultrashort pulses of ∼150 fs with a repetition rate of 1000 Hz was systematically investigated. When pumping a 12-cm-long fiber at a wavelength of 6.5μm with 14 mW pump laser power, a broadband supercontinuum spanning from 2.0μm to 12.7μm with an output power of 300μW was obtained.

抽运波长对中红外超连续谱影响的数值模拟

抽运波长对中红外超连续谱影响的数值模拟

Observation of Brillouin gain spectrum in optical fibers in telecommunication band: Effect of pump wavelength

Observation of Brillouin gain spectrum in optical fibers in telecommunication band: Effect of pump wavelength

Optical parametric amplification in dual-pumped tellurite hybrid microstructured optical fiber with engineered chromatic dispersion

We numerically demonstrated broad and flattened gain spectra of optical parametric amplification employing highly nonlinear tellurite optical fiber and dual-pump configuration. The chromatic dispersion profile of the tellurite hybrid microstructured optical fiber was engineered to be near-zero and flattened, having four zero-dispersion wavelengths at 1421, 1643, 1928 and 2169 nm. The effect of pump wavelength was investigated when the two pump powers were kept at 1 W, the fiber length was 25 cm and the fiber nonlinearity was as high as 6642 W-1km-1. It is shown that OPA gain bandwidth with gain ripples could be as broad as 1393 nm at 10-dB signal gain. When the central pump wavelength approached the third zero- dispersion wavelength and the pump powers were 1.25 W, an ultra-flat (±0.01-dB gain fluctuation) and broad gain bandwidth (658 nm at 30-dB signal gain) could be achieved.

Effect of pump wavelength on Nd^3+:YABself-frequency-doubling laser

The direct and indirect pumping could be used to excite Nd3+-activated crystals effectively. The advantage of direct pumping is the reduction of heat load, and the shortage is the low absorption of pump power. They are the contrary factors affecting the laser performance; hence, the direct pumping is not always better than indirect pumping. To compare the laser performance under direct pumping with that under indirect pumping, the self-frequency-doubling laser model that takes the heat load into account is developed, and the model is applied to the case of Nd3+:YAB crystal. For the typical experimental parameters, we derive the criteria to judge the preferential pumping for the given crystal.

Selection of suitable pump diode laser parameters and their effects on efficiency and optimum length of Yb-doped double clad fiber lasers

The effects of diode laser pump parameters on the fiber laser performance are investigated numerically and experimentally. According to our simulation results, the wide spectrum pump diode laser centered at 976 nm wavelength will reduce the fiber laser optical efficiency and increase the optimal fiber length. The effect of pump wavelength on the fiber laser optical efficiency and the output power stability has also been studied. 976 nm pump wavelength is more efficient but the output power at this wavelength is more dependent on the pump wavelength tolerance. The experimental results are in good agreement with the theoretical ones.

Dependence of performance of saturated in-line erbium-doped fiber amplifiers on pump wavelength around 1480 nm

The effect of pump wavelength around 1480 nm on the performance of saturated erbium-doped fiber amplifiers (EDFAs) suitable for use as in-line amplifiers for terrestrial and submarine systems is investigated experimentally. The results show that for high-gain amplifiers (25 dB) with high output powers (15 dBm), operating around 10 dB in compression, the performance is relatively insensitive to pump wavelength. However, for lower gain amplifiers (12 dB), pumped at low (15 mW) powers, the compression of the amplifier is found to decrease significantly with increasing pump wavelength, while the noise figure shows a weak minimum for a pump wavelength near 1480 nm.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>