In the last decade we have applied with consistent results the integral transform technique in solving the classical heat
equation for determining the thermal fields in laser-solid interaction. In the present paper we apply for the first time this
powerful mathematical instrument for laser-transparent liquids interaction in order to find the thermal field of this
In this paper, some devices were reviewed to be used in quantum communications. We presented a low density of
Quantum Dots, which could be used to get single quantum dot as light emitting source for generating single photons. An
analytical model to study the thermal behavior of a solid media in interaction with one, two or three laser beams was
developed using the classical heat equation. Integrated optic micro-ring resonators and its simulated result also are
presented. Development of active micro-ring in silicon is at an early stage, where both vertical and horizontal techniques
are feasible. With the epitaxy growth techniques, a possibility for achieving controllable QD density, size and good
uniformity are proposed. A low density of QDs in range of 108 cm-2 has demonstrated through successive adjustment of
the growth parameters. Details among the devices are presented and discussed.
The development of masers in the 1950's made possible amplifiers that were much quieter than other contemporary amplifiers. An analysis of narrow-band yields a fundamental theorem (Caves theorem) for phase-insensitive linear amplifiers; it requires that such an amplifier, will add noise as large as half-quantum of zero-point fluctuations. For phase-sensitive linear amplifiers the theorem establish a lower limit on the product of the noises added to the two phases. In the last decade it was shown theoretically that solid-state masers without inversion may be obtained in multilevel spin systems in dilute paramagnetic solids at high temperature subjected to several strong fields. In the present paper the author applies the Caves theorem to the maser without inversion in order to find out the best ways in which the proposed device can work.
In this paper we extend a thermal model of the laser interaction with solids. The previous model [Appl. Phys. B 71, 523-531, (2000)] takes into account Gaussian laser beams and calculate the temperatures only at the center and at the corner of the input face. In the present paper we extent the model for three dimensional temperature profiles and take into account an explicit surface absorption. We will apply the model at CO2 laser interaction with optical components (ZnSe).
In the present paper we are dealing with the thermal fields for laser-metallic thin film interaction. We propose a simplified model which takes into account just one global heat equation instead of two couple heat equations. For the parameters which are the same order of magnitude we take into account just the thermal coefficients of the substrate. The idea of our model is to consider an absorption coefficient as close as possible to reality. We solve the heat equation using the integral transform technique. We plot the thermal field at the interface for different situations. Our results indicate that: (i) the thermal field depends strongly on the absorption coefficient of the thin film and (ii) the length of the interface, at least in the domain 0.1-10 μm does not play an important role in the thermal fields. Specific results are presented for a laser beam operating in the mode TEM01.
The interaction of solids with multiple electromagnetic fields is of great importance in quantum electronics. In this paper the behavior of the heat transfer in a solid irradiated by multiple laser beams is investigated. The directions of laser beams propagation are supposed to be along Cartesian coordinate axes. The spatial distribution of laser beams is supposed to be Gaussian. The model is valid for any laser-solid system whose interaction can be described by the Beer law. Calculations are performed using the integral transform method1,2. The spatial and temporal temperature field distributions are plotted considering a real situation in which ZnSe samples are continuously irradiated with one, respectively three CO2 laser beams.
Laser induced surface cleaning is the adequate method in a large variety of industrial domains as microelectronics, optics, photonics. By comparison to chemical and/or mechanical cleaning, laser cleaning has the advantage of a very good selectivity on the surface and in depth of the material, no surface contamination, without stress in the material volume and environmental safe. It seems that laser cleaning can be developed in a method to be currently used in microelectronic industry. For an efficient laser cleaning of metallic thin films without damage of the silicon wafer, a careful optimization of the incident laser energy, fluence, intensity and number of laser pulses is needed. We have developed an analytical procedure to study the temperature fields in pulsed laser heated solids, for a deeper knowledge of the laser-thin film substrate interaction.
Laser products for medical or industrial use have to be evaluated both for their performances (output power/energy power/energy density, bean characteristics, etc.,) and from laser safety point of view. This paper presents an integrated setup for characterization of the laser systems, by connecting, through a dedicated software, stand alone measurement devices. In our set-up two Spiricon laser beam analyzers: LBA 100 and LBA 300-PC as well as an Orphir LaserStar power/energy meter work under a PC control. Some of the software involved was developed by using the LabVIEW 5.0 graphically programming environment, and allows the user to remotely control the measurement process by virtual instruments.
It is of great importance from the experimental point of view, to understand the thermal behavior of the optical components during how power/energy laser irradiation. The study of the heat transfer in the sample volume is necessary in designing and manufacturing high quality optical components. In this context, we discuss the surface heat transfer coefficients influence on the temperature profile, during CO2 laser irradiation of homogeneous optical components. The assumption of zero heat transfer across the sample radial longitudinal sections is also analyzed. Thermal profiles deduced from the heat diffusion equation are plotted for different heat transfer values.