We report on the demonstration of the effectiveness of nanosecond laser annealing on optical properties of phosphorus ion (P)-implanted ZnO nanorods (NRs). Vertically-alligned ZnO NRs have been synthesized by nanoparticle-assisted pulsed laser deposition (NAPLD) on c-plane sapphire substrates. The pre-laser annealing was performed with the third harmonic (355 nm) of a Qwitched Nd:YAG laser at a...

The modulation response, relative intensity noise (RIN) and frequency noise (FN) characteristics of quantum dot (QD) lasers are investigated theoretically in the presence of an external optical beam. Using small signal analysis of the rate equations for carriers and photons, it is demonstrated that by injecting excess carriers into the QDs excited state through optical pumping, the modulation r...

In this paper, we present a high accuracy laser range finder and velocimeter using ultra-fast time-to-digital converter (TDC). The system operation is based on the measuring the round-trip time of a narrow laser pulse. A low-dark current high-speed PIN photodiode is used to detect the triggered laser beam and to produce start signal. The pulsed laser diode generates 45W optical power at 30ns du...

This study aimed to evaluate Laser-cutting process of Mild Steel St37 sheets with two different thicknesses. In order to evaluate the quality of cutting edge and the depth of the area affected by the heat, several tests were conducted to determine the effect of parameters such as Laser power, Laser beam movement speed and pressure of axillary gas on the quality of cutting edge and the depth of ...

Micro-channels are made over the Ag+/Na+ ion-exchanged soda-lime glass surface by interaction of an intense Ar+ laser beam and the silver ions inside the glass matrix. The Ar+ laser beam reduces the Ag+ ions inside the matrix. The Ag+ atoms aggregate into silver nano-clusters around the interaction area, inside the glass matrix. Aggregation of the silver atoms and the thermal effects of the int...

Nano and femtosecond laser writing are becoming very popular techniques for patterning carbon-based materials, as they are single-step processes enabling the drawing of complex shapes without photoresist. However, pulsed laser writing requires costly laser sources and is known to cause damages to the surrounding material. By comparison, continuous-wave lasers are cheap, stable and provide energ...

Laser diode beam divergence is the main parameter for beam shaping and fiber optic coupling. Increasing the waveguide layer thickness is the conventional method to decrease the beam divergence. In this paper, the broadened asymmetric waveguide is introduced to decrease the divergence without increasing the optical power. The asymmetric waveguide was used to shift the vertical optical field to n...

We present results from laser annealing experiments in Si using a passively Q-switched Nd:YAG microlaser. Exposure with laser at fluence values above the damage threshold of commercially available photodiodes results in electrical damage (as measured by an increase in photodiode dark current). We show that increasing the laser fluence to values in excess of the damage threshold can result in an...