Editing Picosecond

{{Short description|One trillionth of a second}}
{{Infobox unit
| name     = picosecond
| image    = 
| caption  = 
| symbol   = ps
| standard = [[SI]]
| quantity = [[time]]
| units1   = [[SI units]]
| inunits1 = {{val|e=-12|ul=s}}
}}
A '''picosecond''' (abbreviated as '''ps''') is a [[unit of time]] in the [[International System of Units]] (SI) equal to 10<sup>−12</sup> or {{frac|1|1 000 000 000 000}} (one trillionth) of a [[second]].  That is one trillionth, or one millionth of one millionth of a second, or 0.000&nbsp;000&nbsp;000&nbsp;001 seconds.

A picosecond is to one second, as one second is to approximately 31,688.76 years.

Multiple technical approaches achieve imaging within single-digit picoseconds: for example, the [[streak camera]] or [[Intensified charge-coupled device|intensified CCD (ICCD) cameras]] are able to picture the motion of light.<ref>{{cite web|url=http://web.mit.edu/newsoffice/2011/trillion-fps-camera-1213.html|title=Trillion-frame-per-second video|publisher=Massachusetts Institute of Technology|access-date=2014-03-06}}</ref><ref>{{cite web|url=http://www.stanfordcomputeroptics.com/applications/iccd-methods/ultra-high-speed-imaging.html|title=Ultra high speed CCD cameras capture the motion of light.|publisher=Stanford Computer Optics|access-date=2014-03-06}}</ref>

One picosecond is equal to 1000 [[femtosecond]]s, or 1/1000 [[nanosecond]]s.  Because the next SI unit is 1000 times larger, measurements of 10<sup>−11</sup> and 10<sup>−10</sup> second are typically expressed as tens or hundreds of picoseconds.  Some notable measurements in this range include:

* 1.0 picoseconds (1.0 ps) – cycle time for electromagnetic frequency 1 terahertz (THz) (1 x 10<sup>12</sup> hertz), an inverse unit. This corresponds to a wavelength of 0.3&nbsp;mm, as can be calculated by multiplying 1&nbsp;ps by the [[speed of light]] (approximately 3 x 10<sup>8</sup> m/s) to determine the distance traveled. 1 THz is in the [[far infrared]].
* 1 picosecond – time taken by light in vacuum to travel approximately 0.30&nbsp;mm
* 1 picosecond – half-life of a [[bottom quark]]
* ~1 picosecond – lifetime of a single {{chem|H|3|O|+}} ([[hydronium]]) ion in water at 20&nbsp;°C<ref>{{cite web |url= http://bionumbers.hms.harvard.edu/bionumber.aspx?id=106550 |title= Lifetime of single hydronium (H3O+) ion at 20°C |publisher= BioNumbers |access-date=2011-10-10 }}</ref>
* picoseconds to nanoseconds – phenomena observable by [[dielectric spectroscopy]]
* 1.2 picoseconds – switching time of the world's fastest [[transistor]] (845&nbsp;GHz, as of 2006)<ref>{{cite web |author=Kloeppel |first=James E. |date=December 11, 2006 |title=World's Fastest Transistor Approaches Goal of Terahertz Device |url=http://news.illinois.edu/news/06/1211transistor.html |url-status=deviated |archive-url=https://web.archive.org/web/20110427064017/http://news.illinois.edu/news/06/1211transistor.html |archive-date=April 27, 2011 |website=University of Illinois News Bureau |publisher=[[University of Illinois Urbana-Champaign]]}}</ref>
* 1.7 picoseconds – [[rotational correlation time]] of water<ref>{{cite journal|last=Lankhorst|first=D.|author2=Schriever, J. |author3=Leyte, J. C. |title=Determination of the Rotational Correlation Time of Water by Proton NMR Relaxation in H217O and Some Related Results|journal=Berichte der Bunsengesellschaft für physikalische Chemie|year=1982|volume=86|issue=3|pages=215–221|doi=10.1002/bbpc.19820860308}}</ref>
* 3.3 picoseconds (approximately) – time taken for [[light]] to travel 1 [[millimeter]]
* 10 picoseconds after the [[Big Bang]] – [[electromagnetism]] separates from the other [[fundamental force]]s
* 34 picoseconds – signal [[rise time]] (20% to 80%) of a [[SFP+]] transmitter for [[10 Gigabit Ethernet]].<ref>{{cite web|title=SFF-8431 Specifications for Enhanced Small Form Factor Pluggable Module SFP+|author=SFF Committee|url=https://www.10gtek.com/templates/wzten/pdf/SFF-8431-(SFP+%20MSA).pdf}}</ref>
* 10 to 150 picoseconds – [[rotational correlation time]]s of a molecule (184 g/mol) from hot to frozen water<ref>{{Cite journal | last1 = Bulla | first1 = I. | last2 = Törmälä | first2 = P. | last3 = Lindberg | first3 = J. J. | last4 = Mikalsen | first4 = Ø. | last5 = Southern | first5 = J. T. | last6 = Edlund | first6 = K. | last7 = Eliasen | first7 = M. | last8 = Herskind | first8 = C. | last9 = Laursen | first9 = T. | last10 = Pedersen | first10 = P. M. L. | title = Spin Probe Studies on the Dynamic Structure of Dimethyl Sulfoxide-Water Mixtures | journal = Acta Chemica Scandinavica | volume = 29a | pages = 89–92 | year = 1975 | doi = 10.3891/acta.chem.scand.29a-0089| doi-access = free }}</ref>
* 100 picoseconds – [[Unit interval (data transmission)|Unit Interval]] of a 10 Gbit/s [[serial communication]] link, such as [[USB 3.1]].<ref>{{cite web|title=Universal Serial Bus 3.1 Specification|url=https://manuais.iessanclemente.net/images/b/bc/USB_3_1_r1.0.pdf}}</ref>
* 108.7827757 picoseconds – transition time between the two hyperfine levels of the ground state of the [[Caesium#Isotopes|caesium-133]] atom at [[absolute zero]]
* 330 picoseconds (approximately) – the time it takes a common 3.0 [[GHz]] computer [[CPU]] to complete a processing cycle

==See also==
* [[SI unit]]
* [[Second]]
* [[Nanosecond]]
* [[Microsecond]]
* [[Millisecond]]
* [[Jiffy (time)]]
* [[Orders of magnitude (time)]]

==References==
{{reflist}}

==External links==
*[https://www.nist.gov/pml/div688/grp40/enc-p.cfm National Institute for Standards and Technology Glossary]

{{Orders of magnitude seconds}}

[[Category:Orders of magnitude (time)]]

[[fr:1 E-12 s]]