A Ho3+-doped photonic crystal fiber laser with output wavelength of 2077nm has been demonstrated using a 1992nm Tm3+-doped fiber laser with output wavelength of 1992nm as a pump source. And the optical- optical conversion slope efficiency is 41.3%. In order to optimize the output power of the Ho3+-doped photonic crystal fiber laser, a simple quasi-three level system theoretical modeling is developed in the condition of Stark-splitted energy level diagram of holmium ion. We obtain the theoretical optical- optical conversion slope efficiency 43.5%, which is higher than the experimental 41.3%. Furthermore, the relative deviation of the η is 5%, which shows the theoretical data is good agreement with experimental data. According to the modeling, the influence factors of the output power have been theoretically studied, in detail. The results show that there are an optimal range of Ho3+-doped concentration n0, transmittance of coupled output mirror T2 and length of the PCF L, respectively. Furthermore, the output power is approximately equal to maximum in the range of the optimal value.
A laser-diode-pumped actively Q-switched Yb:NaY(WO4)2 laser operating at around 1040 nm is presented for the first time with acoustic-optic modulator. The dependence of pulse width on incident pump power for different pulse repetition rates is measured. By considering the Guassian spatial distribution of the intracavity photon density and the initial population-inversion density as well as the longitudinal distribution of the photon density along the cavity axis and the turn off time of the acoustic-optic Q-switch, the coupled equations of the actively Q-switched Yb:NaY(WO4)2 laser are given. The coupled rate equations are used to simulate the Q-switched process of laser, and the numerical solutions agree with the experimental results.
A KTP EOPO pumped by an AO Q-switched and SESAM mode-locked Nd3+: GdVO4 laser is experimentally realized.
The cavity is designed to satisfy synchronously pump. The signal trace and output powers from the OPO are
experimentally measured. Based on the experiment, a dynamical rate-equation model is firstly set to simulate the
operation of the Q-switched and mode-locked OPO. The theoretical values from the rate equations agree with the
experimental results well. The developed model explains the behavior, which is helpful to system optimization.
In order to investigate the power characteristics of the Yb-doped photonic crystal fiber(PCF) laser, we have represented a simple three-level system modeling based on a rate equation model. According to our theoretical modeling, the variation of the output power Pout via the pump power Pp is theoretically studied, which agrees well with experimental data. Then, we have investigated the effects of the doped concentration of Yb ions, the length and the effective mode field area of the PCF on the output power Pout of the Yb-doped PCF laser, respectively. The results show that the output power Pout first increases and then decreases when the doped concentration of Yb ions N0 increases and when the pump power Pp and the length of the PCF L are constant. And the optimal doped concentration Nm exponentially decreases when the length L of the PCF increases and the slope of the optimal doped concentration Nm also decreases when the length L of the PCF increases. The output power Pout first increases and then decreases when the length of the PCF L increases and when the pump power Pp and the doped concentration N0 are constant. And the optimal length Lm of the PCF exponentially decreases when the doped concentration N0 increases and the slope of the length of the PCF also decreases when the doped concentration N0 increases. The output power Pout linearly decreases when the effective mode field area A increases.
We report on the fabrication and characterization of KTiOPO4 optical waveguides formed by Rb+-K+ ion exchange in high-purity RbNO3 melt at 340°C for 90 min and subsequent He+-ion irradiation at energy of 500 keV and fluence of 3×1016 ions/cm2. The irradiation of KTiOPO4 crystals with He+ ions was simulated using the stopping range of ions in matter (SRIM’2006) software. The dark mode spectra of the samples were measured with the prism coupling method. The reconstructed refractive index profiles of the planar waveguide show a barrier in the middle of the guiding region, and a refractive index enhancement region on each side of the barrier, indicating the formation of a double waveguide.
One provides a simple recipe, which is manipulating refractive of doped region of the MCPCF, to obtain the equal
amplitude distribution of the in-phase supermode for multicores photonic crystal fibers (MCPCFs). Using coupled mode theory and vector finite element method (VFEM), a 7-core PCF is analyzed in detail and the results are applied to 16-,18- and 19-core PCFs, which will find important applications in high-power MCPCF lasers and amplifiers. One shows that it is possible to construct uniformly distributed modes for the nontrivial examples of 7- 16-, 18- and 19-core PCFs. One demonstrates that an equal amplitude distribution of in-phase supermode can be achieved by manipulating refractive of doped region in cores area. This research would provide a theoretical basis for investigating equal amplitude in-phase supermode in the MCPCF.
Using both Cr4+:YAG and GaAs saturable absorbers in the same cavity, a diode-pumped doubly passively Q-switched
Nd:YVO4 laser is realized. Compared with the solely passively Q-switched laser Cr4+:YAG or GaAs, the pulse shape of doubly Q-switched laser is more symmetric and the pulse duration is compressed. The technique to control the pulse
duration has been studied. With different position of the saturable absorber, the pulse duration changes in the range from
41.8ns to 118ns at the pump power of 4.47W, respectively. A rate equation model is introduced to theoretically analyze
the results obtained in the experiment, in which the Gaussian spatial distribution of the intracavity photon density and the
longitudinal variation of the photon density are taken into account. The numerical calculations of the rate equations are
consistent with the experimental results.
By considering the AO switch as a low speed switch and the AO turnoff time including the transit time of the acousticwave
and the electronic turnoff time as well as the Gaussian spatial distribution of the intra-cavity photon density, the
coupled equations of a Laser-diode pumped actively Q-switched Nd:YVO4 laser with acoustic-optic modulator are
given. By changing the position of AO in the cavity for changing the transit time of the acoustic-wave, the effect of the
AO transit time on the characteristics of the output Q-switched pulse is obtained. It is show that the longer transit time
leads to the wider pulse duration. In the experiment, a laser-diode-pumped actively Q-switched Nd:YVO4 laser with
acoustic-optic modulator is realized, and the experimental results are in fair agreement with the numerical solutions.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.