Neologism include "laser" (1960) from Light Amplification by Stimulated Emission of Radiation, "robotics" (1941), "agitprop" (1930). The term "neologism" is first attested in English in 1772, borrowed from French "néologisme" (1734). A proponent of a new word or doctrine may be called a neologist. Neologists might study cultural and ethnic vernacular. The term "neologism" has a broader meaning that includes not only "an entirely new lexical item" but also an existing word whose meaning has been altered. Sometimes, the latter process is called "semantic shifting", or "semantic extension". Neologisms are distinct from a person's "idiolect", one's unique patterns of vocabulary, grammar,
Sound amplification by stimulated emission of radiation tend to emit phonons randomly. Researchers have overcome the problem of terahertz frequencies by following various approaches. Scientists in Caltech have overcome this problem by assembling a pair of microscopic cavities that only permit specific frequencies of phonons to be emitted. This system can be also tuned to emit phonons of different frequencies by changing the relative separation of the microcavities. On the other hand, the group from the University of Nottingham took a different approach. They have built their device out of electrons moving through a series of structures known as quantum wells. Briefly, as an electron hops from