The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm), or nanometer (American spelling), is a unit of length in the International System of Units (SI), equal to one billionth (short scale) or one thousand million (long scale) of a meter (0.000000001 m) and to 1000 picometres. One nanometre can be expressed in scientific notation as 1 × 10−9 m and as 1/1000000000 m.
| nanometre | |
|---|---|
 One nanometric carbon nanotube, photographed with scanning tunneling microscope | |
| General information | |
| Unit system | SI |
| Unit of | length |
| Symbol | nm |
| Conversions | |
| 1 nm in ... | ... is equal to ... |
| SI units | 1×10−9 m 1×103 pm |
| Natural units | 6.1877×1025 ℓP 18.897 a0 |
| imperial/US units | 3.9370×10−8 in |
History
The nanometre was formerly known as the "millimicrometre" – or, more commonly, the "millimicron" for short – since it is 1/1000 of a micrometer. It was often denoted by the symbol mμ or, more rarely, as μμ (however, μμ should refer to a millionth of a micron).
Etymology
The name combines the SI prefix nano- (from the Ancient Greek νάνος, nanos, "dwarf") with the parent unit name metre (from Greek μέτρον, metron, "unit of measurement").
Usage
Nanotechnologies are based on physical processes which occur on a scale of nanometres (see nanoscopic scale).
The nanometre is often used to express dimensions on an atomic scale: the diameter of a helium atom, for example, is about 0.06 nm, and that of a ribosome is about 20 nm. The nanometre is also commonly used to specify the wavelength of electromagnetic radiation near the visible part of the spectrum: visible light ranges from around 400 to 700 nm. The ångström, which is equal to 0.1 nm, was formerly used for these purposes.
Since the late 1980s, in usages such as the 32 nm and the 22 nm semiconductor node, it has also been used to describe typical feature sizes in successive generations of the ITRS Roadmap for miniaturized semiconductor device fabrication in the semiconductor industry.
Unicode
The CJK Compatibility block in Unicode has the symbol U+339A ㎚ SQUARE NM.
References
- Svedberg T, Nichols JB (1923). "Determination of the size and distribution of size of particle by centrifugal methods". Journal of the American Chemical Society. 45 (12): 2910–2917. doi:10.1021/ja01665a016.
- Svedberg T, Rinde H (1924). "The ulta-centrifuge, a new instrument for the determination of size and distribution of size of particle in amicroscopic colloids". Journal of the American Chemical Society. 46 (12): 2677–2693. doi:10.1021/ja01677a011.
- Terzaghi K (1925). Erdbaumechanik auf bodenphysikalischer Grundlage. Vienna: Franz Deuticke. p. 32.
- Hewakuruppu YL, Dombrovsky LA, Chen C, Timchenko V, Jiang X, Baek S, Taylor RA (2013). "Plasmonic " pump – probe " method to study semi-transparent nanofluids". Applied Optics. 52 (24): 6041–6050. Bibcode:2013ApOpt..52.6041H. doi:10.1364/AO.52.006041. PMID 24085009.
External links
- Near-field Mie scattering in optical trap nanometry
The nanometre international spelling as used by the International Bureau of Weights and Measures SI symbol nm or nanometer American spelling is a unit of length in the International System of Units SI equal to one billionth short scale or one thousand million long scale of a meter 0 000000001 m and to 1000 picometres One nanometre can be expressed in scientific notation as 1 10 9 m and as 1 1000 000 000 m nanometreOne nanometric carbon nanotube photographed with scanning tunneling microscopeGeneral informationUnit systemSIUnit oflengthSymbolnmConversions1 nm in is equal to SI units 1 10 9 m 1 103 pm Natural units 6 1877 1025 ℓP 18 897 a0 imperial US units 3 9370 10 8 inDifferent lengths as in respect to the electromagnetic spectrum measured by the metre and its derived scales The nanometre is often used to express dimensions on an atomic scale and mostly in the molecular scale HistoryThe nanometre was formerly known as the millimicrometre or more commonly the millimicron for short since it is 1 1000 of a micrometer It was often denoted by the symbol mm or more rarely as mm however mm should refer to a millionth of a micron EtymologyThe name combines the SI prefix nano from the Ancient Greek nanos nanos dwarf with the parent unit name metre from Greek metron metron unit of measurement UsageNanotechnologies are based on physical processes which occur on a scale of nanometres see nanoscopic scale The nanometre is often used to express dimensions on an atomic scale the diameter of a helium atom for example is about 0 06 nm and that of a ribosome is about 20 nm The nanometre is also commonly used to specify the wavelength of electromagnetic radiation near the visible part of the spectrum visible light ranges from around 400 to 700 nm The angstrom which is equal to 0 1 nm was formerly used for these purposes Since the late 1980s in usages such as the 32 nm and the 22 nm semiconductor node it has also been used to describe typical feature sizes in successive generations of the ITRS Roadmap for miniaturized semiconductor device fabrication in the semiconductor industry UnicodeThe CJK Compatibility block in Unicode has the symbol U 339A SQUARE NM ReferencesSvedberg T Nichols JB 1923 Determination of the size and distribution of size of particle by centrifugal methods Journal of the American Chemical Society 45 12 2910 2917 doi 10 1021 ja01665a016 Svedberg T Rinde H 1924 The ulta centrifuge a new instrument for the determination of size and distribution of size of particle in amicroscopic colloids Journal of the American Chemical Society 46 12 2677 2693 doi 10 1021 ja01677a011 Terzaghi K 1925 Erdbaumechanik auf bodenphysikalischer Grundlage Vienna Franz Deuticke p 32 Hewakuruppu YL Dombrovsky LA Chen C Timchenko V Jiang X Baek S Taylor RA 2013 Plasmonic pump probe method to study semi transparent nanofluids Applied Optics 52 24 6041 6050 Bibcode 2013ApOpt 52 6041H doi 10 1364 AO 52 006041 PMID 24085009 External linksLook up nanometre in Wiktionary the free dictionary Near field Mie scattering in optical trap nanometry
