Laser science

quantum mechanical state change

process by which an incoming photon of a specific frequency can interact with an excited atomic electron (or other excited molecular state), causing it to drop to a lower energy level

state of a physical system in which more members are in higher, excited energy states than in lower, unexcited states

dimensionless measure for the damping of an oscillator

device that amplifies an optical signal

temperature of a physical system with a bounded phase space that is hotter than one at infinite temperature (𝛽=0)

field of radiation (e.g. electromagnetic wave) whose amplitude is described by the Gaussian function

arrangement of mirrors that forms a standing wave cavity resonator for light waves

method of radio transmission, in which a sinusoidal carrier wave is switched on and off. Information is carried in the varying duration of the on and off periods of the signal, e.g. by Morse code

Q-switching, sometimes known as giant pulse formation or Q-spoiling, is a technique by which a laser can be made to produce a pulsed output beam. The technique allows the production of light pulses with extremely high (gigawatt) peak power, much higher than would be produced by the same laser if it were operating in a continuous wave (constant output) mode. Compared to mode locking, another technique for pulse generation with lasers, Q-switching leads to much lower pulse repetition rates, much higher pulse energies, and much longer pulse durations. The two techniques are sometimes applied toge

laser source emitting in equally spaced frequency lines

quantum system that allows amplification of power (gain) of waves passing through

branch of optics that describes the theory and practice of lasers

technique for amplifying an ultrashort laser pulse

physical process in which a thermal gradient causes different parts of an object to expand by different amounts

way to produce very short laser bursts

Optical component

laser pulse with duration a picosecond (10−12 s) or less

electromagnetic wave with oscillations perpendicular to the direction of travel

laser science process

radiation whose amplitude is described by a Bessel function of the first kind

any laser not classified as continuous wave

concept in laser optics

thumb|Figure 1. A typical supercontinuum spectrum. The blue line shows the spectrum of the pump source launched into a photonic crystal fiber while the red line shows the resulting supercontinuum spectrum generated after propagating through the fiber. thumb|Image of a typical supercontinuum. This supercontinuum was generated by focusing 800 nm, sub-100 fs pulses into a yttrium aluminium garnet (YAG) crystal, generating ultra broadband light that spans both the visible and NIR. In optics, a supercontinuum is formed when a collection of nonlinear processes act together upon a pump beam in order

powering mechanism for lasers

structure formed by reflecting faces

thumb|250px|Light passing through a gradient-index optics|gradient-index lens is focused as in a convex lens. In self-focusing, the refractive index gradient is induced by the light itself. Self-focusing is a non-linear optical process induced by the change in refractive index of materials exposed to intense electromagnetic radiation. A medium whose refractive index increases with the electric field intensity acts as a focusing lens for an electromagnetic wave characterized by an initial transverse intensity gradient, as in a laser beam. The peak intensity of the self-focused region keeps incr

field of radiation (e.g. electromagnetic wave) whose amplitude is described by a product of the Airy function of the first kind and an exponent

Inelastic optical scattering phenomenon

type of laser light source that emits light of variable wavelengths

quantum effect of uncertainty

guide star instrument used by the U.S. Air Force

process within a free-electron laser by which a laser beam is created by the high-energy electron beam

type of laser

light optically amplified by stimulated emission

difference between a laser frequency and a resonant frequency