What is the waist of a Gaussian beam?
Figure 1: The waist of a Gaussian beam is defined as the location where the irradiance is 1/e2 (13.5%) of its maximum value. In the above equations, λ is the wavelength of the laser and θ is a far field approximation.
Is Gaussian beam a plane wave?
Gaussian beam can describe both planewave-like behavior at near field and give spherical-wave-like at farfield. Gaussian beam is an exact solution to the paraxial approximation of the Helmholtz Eq. and it is an approximated solution to the exact Helmholtz Eq.
How is the beam waist w of a Gaussian laser beam defined?
What is the beam waist?
The beam waist (or beam focus) of a laser beam is the location along the propagation direction where the beam radius has a minimum. The waist radius is the beam radius at that location. Figure 1: The beam waist is the location where the beam radius is smallest.
What is meant by Gaussian beam?
In optics, a Gaussian beam is a beam of electromagnetic radiation with high monochromaticity whose amplitude envelope in the transverse plane is given by a Gaussian function; this also implies a Gaussian intensity (irradiance) profile.
What is Gaussian beam and its properties?
The Gaussian is a radially symmetrical distribution whose electric field variation is given by the following equation: r is defined as the distance from the center of the beam, and ω0 is the radius at which the amplitude is 1/e of its value on the axis.
What are Gaussian beams used for?
Importance of Gaussian Beams Gaussian beams are the lowest-order self-consistent field distribution in optical resonators (→ resonator modes) provided that there are no intracavity elements causing beam distortions. For that reason, the output beams of many lasers are Gaussian.
What is Gaussian in a Gaussian beam?
Gaussian modes are the lowest order modes of an optical resonator, set along the transverse direction. A stable resonator will have homogeneous optical media, and a flat or parabolic surface between the media. Hence, lasers in the fundamental transverse mode often emit beams close to Gaussian shape.
What is a plane wave basis set?
Bloch’s theorem states that the electronic wavefunctions at each k-point can be expanded in terms of a discrete plane-wave basis set. In principle, an infinite number of plane waves is required for such an expansion.
What are the characteristics of plane wave?
Plane waves are a special case of waves where a physical quantity, such as phase, is constant over a plane that is perpendicular to the direction of wave travel. Just like periodic waves, plane waves have a wavelength, frequency, and wave speed.
What are the properties of Gaussian beam?
The importance of Gaussian beams results from a number of special properties:
- Gaussian beams have a Gaussian intensity profile at any location along the beam axis; only the beam radius varies.
- A Gaussian beam remains Gaussian also after passing simple kinds of optical elements (e.g. lenses without optical aberrations).