Half a century since the first working laser kick-started a technological revolution in the field of optics, a new device promises to do the same for acoustics. UK and Ukrainian physicists have built the first "saser", or sound laser, able to generate terahertz-frequency sounds.
A laser produces photons that travel in a tight beam instead of dispersing outwards like a regular beam of light. A saser achieves the same for sound waves, says Tony Kent at the University of Nottingham, UK.
Although it's not the first saser ever constructed, it is the first able to produce beams at terahertz frequencies, much higher even than those used for medical ultrasound imaging. Terahertz sound may be largely a curiosity today, says Kent, but being able to produce it in controllable beams could unleash new ideas and applications.
"Fifty years ago many eminent scientists said that light amplification by the stimulated emission of radiation [lasers] was no more than a scientific curiosity," says Kent, but lasers are now used for everything from digital storage and cancer treatment to weaponry.
For the rest of the article, click here...
FTP Consultancy
Be sure to consult a dictionary as some of the words below have other meanings not described here.
1. everyday, every day: The adjective everyday means “commonplace or ordinary”; “suitable for routine occasions”. The phrase every day means “each day”.
Though every day brings everyday occurrences, once in a while inexplicable things happen – if you but pay attention.
2. everyone, every one: Everyone is an indefinite pronoun meaning “every person”; “everybody”. In the phrase every one, the pronoun one is modified by the adjective every to mean “each individual or thing in a particular group”.
Everyone must continue working until every one of those rugs are cleaned.
3. explicit, implicit: The adjective explicit means “expressed directly with clarity, forthrightness, and precision”. Implicit is an adjective that means “implied or unstated, though not directly expressed”.
The chef gave explicit instructions on how to prepare the Lasagna.
The disapproval was implicit in the way he shrugged his shoulders.
For the rest of the words, click here...
FTP Consultancy
