What is a semiconducting laser How does it work?
Introduction. A semiconductor laser (LD) is a device that causes laser oscillation by flowing an electric current to semiconductor. The mechanism of light emission is the same as a light-emitting diode (LED). Light is generated by flowing the forward current to a p-n junction.
What kind of semiconductor we use for laser?
The material which often used in semiconductor laser is the gallium Arsenide, therefore semiconductor laser is sometimes known as Gallium Arsenide Laser. It is also called Injection Laser.
What are semiconductor lasers used for?
Such characteristics make semiconductor lasers the most important type of lasers, technologically speaking. Their applications are extremely widespread and include optical telecommunications, optical data storage, metrology, spectroscopy, material processing, pumping of other lasers, and medical treatments.
What is hetero junction semiconductor laser?
Heterojunction Lasers : two interfaces of different indexes of refraction, one on top and one below the active region, so two junctions are formed in what is called a heterostructure laser diode, or a double heterostructure, since there are two confining interfaces.
What are the advantages of semiconductor laser?
The advantages of semiconductor lasers are: small volume, lightweight, good reliability, long service life, and low power consumption. In addition, semiconductor laser adopted low voltage constant current power supply mode, hence provided low powder failure rate, safe operation, and low cost of maintenance.
What is a semiconducting material?
Semiconductors are materials which have a conductivity between conductors (generally metals) and nonconductors or insulators (such as most ceramics). Semiconductors can be pure elements, such as silicon or germanium, or compounds such as gallium arsenide or cadmium selenide.
Is semiconductor laser a 3 level laser?
Note that the gain media of semiconductor lasers actually also behave like three-level lasers, exhibiting losses in the unpumped state and a shape of the gain spectrum which depends on the excitation density.
What is semiconductor hetero junction?
A heterojunction is an interface between two layers or regions of dissimilar semiconductors. These semiconducting materials have unequal band gaps as opposed to a homojunction.
What are the advantages of heterojunction?
This structure allows to collect more energy out of the solar radiation. As a result the cells have a higher efficiency. Moreover, it has a lower temperature coefficient allowing better performance at high temperature. On top of that, heterojunctions cells are bifacial.
What are the advantages and disadvantages of semiconductor laser?
What are the limitations of semiconductor lasers?
Following are the drawbacks or disadvantages of Semiconductor Laser: ➨This laser is not suited for many applications due to its low power production. ➨The temperature affects its output. ➨The output beam profile has unusual shape due to lasing medium’s too short size and rectangular shape.
What are semiconductor lasers?
Semiconductor lasers are solid-state lasers based on semiconductor gain media, where optical amplification is usually achieved by stimulated emission at an interband transition under conditions of a high carrier density in the conduction band.
What is the active medium in semiconductor laser?
In this laser semiconductors like GaAs, InP, GaN etc. are used as the active medium and population inversion is achieved by forward biasing the semiconductor. What is the material used in semiconductor laser? What is semiconductor laser? What are the advantages of semiconductor laser? Semiconductor lasers are basically PN junction diode.
How is LED light generated in a semiconductor laser?
Light is generated in a semiconductor laser by radiative recombination of electrons and holes. In order to generate more light by stimulated emission than is lost by absorption, the system has to be inverted, see the article on lasers. A laser is, thus, always a high carrier density system that entails many-body interactions.
What is the band gap of a semiconductor laser?
The band gap of the semiconductor laser is different and hence light of different wavelengths is emitted by this laser. For example band gap of GaAs is 1.42 eV at room temperature and laser light of a wide range of wavelengths from near-infrared region to the visible region of e.m. spectrum is emitted by a laser made of GaAs.