Picosecond

A picosecond is 10⁻¹² of a second. 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 31,700 years.

The name is formed by the SI prefix pico and the SI unit second. It is abbreviated as ps.

One picosecond is equal to 1000 femtoseconds, or 1/1000 nanosecond. 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:

• shorter times

• 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 (approximately 3 x 10⁸ m/s) to determine the distance traveled.
• 1 picosecond – half-life of a bottom quark
• ~1 picosecond – lifetime of a single H₃O⁺ (hydronium) ion in water at 20°C^[1]
• picoseconds to nanoseconds - phenomena observable by dielectric spectroscopy
• 1.2 picoseconds – switching time of the world's fastest transistor (845 GHz, as of 2006)^[2]
• 1.7 picoseconds - rotational correlation time of water^[3]
• 3.3 picoseconds (approximately) – time taken for light to travel 1 millimeter
• 10 picoseconds after the Big Bang – electromagnetism separates from the other fundamental forces
• 10-150 picoseconds - rotational correlation times of a molecule (184 g/mol) from hot to frozen water^[4]
• 108.7827757 picoseconds – transition time between the two hyperfine levels of the ground state of the caesium-133 atom at absolute zero
• 330 picoseconds (approximately) – the time it takes a common 3.0 GHz computer CPU to add two integers

• Longer times

References

National Institute for Standards and Technology Glossary