A picosecond (abbreviated as ps) is a

unit of time A unit of time is any particular time interval, used as a standard way of measuring or expressing duration. The base unit of time in the International System of Units (SI) and by extension most of the Western world, is the second, defined as a ...

in the

International System of Units The International System of Units, known by the international abbreviation SI in all languages and sometimes pleonastically as the SI system, is the modern form of the metric system and the world's most widely used system of measurement. E ...

(SI) equal to 10⁻¹² or (one trillionth) of a

second The second (symbol: s) is the unit of time in the International System of Units (SI), historically defined as of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds ...

. That is one trillionth, or one millionth of one millionth of a second, or 0.000 000 000 001 seconds. A picosecond is to one second as one second is to approximately 31,689 years. Multiple technical approaches achieve imaging within single-digit picoseconds: for example, the

streak camera A streak camera is an instrument for measuring the variation in a pulse of light's intensity with time. They are used to measure the pulse duration of some ultrafast laser systems and for applications such as time-resolved spectroscopy and LID ...

or intensified CCD (ICCD) cameras are able to picture the motion of light. One picosecond is equal to 1000

femtosecond A femtosecond is a unit of time in the International System of Units (SI) equal to 10 or of a second; that is, one quadrillionth, or one millionth of one billionth, of a second. For context, a femtosecond is to a second as a second is to about 31. ...

s, or 1/1000

nanosecond A nanosecond (ns) is a unit of time in the International System of Units (SI) equal to one billionth of a second, that is, of a second, or 10 seconds. The term combines the SI prefix ''nano-'' indicating a 1 billionth submultiple of an SI unit ( ...

s. Because the next SI unit is 1000 times larger, measurements of 10⁻¹¹ and 10⁻¹⁰ 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 10¹² hertz), an inverse unit. This corresponds to a wavelength of 0.3 mm, as can be calculated by multiplying 1 ps by the

speed of light The speed of light in vacuum, commonly denoted , is a universal physical constant that is important in many areas of physics. The speed of light is exactly equal to ). According to the special theory of relativity, is the upper limit ...

(approximately 3 x 10⁸ m/s) to determine the distance traveled. 1 THz is in the

far infrared Far infrared (FIR) is a region in the infrared spectrum of electromagnetic radiation. Far infrared is often defined as any radiation with a wavelength of 15 micrometers (μm) to 1 mm (corresponding to a range of about 20 THz to ...

. * 1 picosecond – time taken by light in a vacuum to travel approximately 0.30 mm * 1 picosecond – half-life of a

bottom quark The bottom quark or b quark, also known as the beauty quark, is a third-generation heavy quark with a charge of − ''e''. All quarks are described in a similar way by electroweak and quantum chromodynamics, but the bottom quark has exc ...

* ~1 picosecond – lifetime of a single (

hydronium In chemistry, hydronium (hydroxonium in traditional British English) is the common name for the aqueous cation , the type of oxonium ion produced by protonation of water. It is often viewed as the positive ion present when an Arrhenius acid is d ...

) ion in water at 20 °C * picoseconds to nanoseconds – phenomena observable by

dielectric spectroscopy Dielectric spectroscopy (which falls in a subcategory of impedance spectroscopy) measures the dielectric properties of a medium as a function of frequency.Kremer F., Schonhals A., Luck W. Broadband Dielectric Spectroscopy. – Springer-Verlag, 200 ...

* 1.2 picoseconds – switching time of the world's fastest

transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch e ...

(845 GHz, as of 2006) * 1.7 picoseconds -

rotational correlation time Rotational correlation time (\tau_c) is the average time it takes for a molecule to rotate one radian. In solution, rotational correlation times are in the order of picoseconds. For example, the \tau_c = 1.7 ps for water, and 100 ps for a pyrroli ...

of water * 3.3 picoseconds (approximately) – time taken for

light Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 tera ...

to travel 1

millimeter 330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter. The millimetre (American and British English spelling differences#-re, -er, ...

* 10 picoseconds after the

Big Bang The Big Bang event is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models of the Big Bang explain the evolution of the observable universe from the ...

–

electromagnetism In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of a ...

separates from the other

fundamental force In physics, the fundamental interactions, also known as fundamental forces, are the interactions that do not appear to be reducible to more basic interactions. There are four fundamental interactions known to exist: the gravitational and electrom ...

s * 34 picoseconds - signal

rise time In electronics, when describing a voltage or current step function, rise time is the time taken by a signal to change from a specified low value to a specified high value. These values may be expressed as ratiosSee for example , and . or, equivale ...

(20% to 80%) of a

SFP+ Small Form-factor Pluggable connected to a pair of fiber-optic cables Small Form-factor Pluggable (SFP) is a compact, hot-pluggable network interface module format used for both telecommunication and data communications applications. An SF ...

transmitter for

10 Gigabit Ethernet 10 Gigabit Ethernet (10GE, 10GbE, or 10 GigE) is a group of computer networking technologies for transmitting Ethernet frames at a rate of 10 gigabits per second. It was first defined by the IEEE 802.3ae-2002 standard. Unlike previous Eth ...

. * 10–150 picoseconds –

s of a molecule (184 g/mol) from hot to frozen water * 100 picoseconds -

Unit Interval In mathematics, the unit interval is the closed interval , that is, the set of all real numbers that are greater than or equal to 0 and less than or equal to 1. It is often denoted ' (capital letter ). In addition to its role in real analysis, ...

of a 10 Gbps

serial communication In telecommunication and data transmission, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are ...

link, such as

USB 3.1 USB 3.0, released in November 2008, is the third major version of the Universal Serial Bus (USB) standard for interfacing computers and electronic devices. Among other improvements, USB 3.0 adds the new transfer rate referred to as '' ...

. * 108.7827757 picoseconds – transition time between the two hyperfine levels of the ground state of the

caesium-133 Caesium (55Cs) has 40 known isotopes, making it, along with barium and mercury, one of the elements with the most isotopes. The atomic masses of these isotopes range from 112 to 151. Only one isotope, 133Cs, is stable. The longest-lived radioisoto ...

atom at

absolute zero Absolute zero is the lowest limit of the thermodynamic temperature scale, a state at which the enthalpy and entropy of a cooled ideal gas reach their minimum value, taken as zero kelvin. The fundamental particles of nature have minimum vibration ...

* 330 picoseconds (approximately) – the time it takes a common 3.0

GHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

computer CPU to complete a processing cycle

References

External links

National Institute for Standards and Technology Glossary
{{Orders of magnitude seconds Orders of magnitude (time) fr:1 E-12 s

See also

References

External links