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Optical phonons are phonon polarization modes with a minimum frequency, regardless of wavelength, which occur in crystals with more than one atom per primitive cell.
Primitive cell is the early technological development....
Wiki User
∙ 16y ago
Wiki User
∙ 14y agobecause their frequency in the range of infra-red 10^13 HZ.
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What is phonon effect?
A phonon is a collective vibrational mode in an ideal crystalline solid. A single phonon is pure vibrational mode. It is direct analogy to a pure vibrational mode in a musical instrument such as a string of a guitar. It can be said that it is a sound wave, but the vibrations allowed that are pure single mode vibrations are more extensive than simple sound waves. Phonons, in their original and normal sense, occur in perfect crystalline structures where each atom has a specific equilibrium location that is repeated regularly in space. In a pure single phonon mode there is a periodic vibration (i.e. displacement) of each atom that is described as a sinusoidal variation in space and time. One specifies a particular phonon with a wavelength, direction and frequency, just as with a sound wave. In real solids, there are imperfections, but they are near enough to idea that the idealized concept of a phonon is usually completely adequate. Finally, phonons can be described as classical vibrations as is natural in classical mechanics and they can be described as quantum vibrations using quantum mechanics. The quantum description is fundamentally correct, but the classical description is very useful and convenient in many cases. Some people would say that you should not call the collective vibrations of a solid phonons unless you are describing them as a quantum phenomena but other people would say that is too picky. Usually, however, the term phonon implies that quantum nature of the vibration of a crystal.
Why efficiency of solar photovoltaic cell is not 100 percent?
Because semiconductors such as silicon are indirect bandgap semiconductors, so some of the light energy is wasted as lattice vibrations (phonons).
Why do some isomers lack optical activity?
doesnt have the right number of neutrons
Does a substance having high optical density have to have a high physical density?
It's not necessary. If a compound has high optical density, it means that it absorbs more light at the given wavelength than some reference compound. There is no simple relation between density of matter and optical density. Even more I am pretty sure you can find a lot of compounds with lower densities (of matter) but having high optical density.
What are some examples of items with low conductivity?
Thermal resistance: diamond Electrical resistance: copper Optical resistance: quartz
What is phonon effect?
A phonon is a collective vibrational mode in an ideal crystalline solid. A single phonon is pure vibrational mode. It is direct analogy to a pure vibrational mode in a musical instrument such as a string of a guitar. It can be said that it is a sound wave, but the vibrations allowed that are pure single mode vibrations are more extensive than simple sound waves. Phonons, in their original and normal sense, occur in perfect crystalline structures where each atom has a specific equilibrium location that is repeated regularly in space. In a pure single phonon mode there is a periodic vibration (i.e. displacement) of each atom that is described as a sinusoidal variation in space and time. One specifies a particular phonon with a wavelength, direction and frequency, just as with a sound wave. In real solids, there are imperfections, but they are near enough to idea that the idealized concept of a phonon is usually completely adequate. Finally, phonons can be described as classical vibrations as is natural in classical mechanics and they can be described as quantum vibrations using quantum mechanics. The quantum description is fundamentally correct, but the classical description is very useful and convenient in many cases. Some people would say that you should not call the collective vibrations of a solid phonons unless you are describing them as a quantum phenomena but other people would say that is too picky. Usually, however, the term phonon implies that quantum nature of the vibration of a crystal.
What is the smallest unit of sound wave energy?
The smallest unit of sound wave energy is the phonon. The phonon and the photon and the electron can in some ways all behave like a small particle.
What are some words that start with opt?
Some words that start with opt are: option, optimal, optician, optimize.
What is some information on optical illusions?
optical illusions are an object causing false impressions
What is an easy definition of the optical axis?
An optical axis is a line along which there is some degree of rotational symmetry in an optical system such as a camera lens or microscope..
What is optical hardware?
Optical networking hardware entails the various components used in optical technologies. Some of the common hardware include routers, optical fiber, electronic devices and so much more.
Why efficiency of solar photovoltaic cell is not 100 percent?
Because semiconductors such as silicon are indirect bandgap semiconductors, so some of the light energy is wasted as lattice vibrations (phonons).
What is optical track pad?
An optical trackpad senses touch, like on the HTC desire. and some Blackberrys.
What is optical networking hardware?
Optical networking hardware entails the various components used in optical technologies. Some of the common hardware include routers, optical fiber, electronic devices and so much more.
What uses a device that emit and sense light to detect the mouse's movement?
Optical mouse: Most desktop computer users today have some type of optical mouse, which uses devices that emit and sense light to detect the mouse's movement.
What is some materials for the optical illusions?
hologram
What is an image called that when you turn it upside down is another distinguishable image For a simple example when you flip some font's M's upside down you'll get a W.?
This could be called optical illusions.
