H-b index
Encyclopedia
The h-b-index is an extension of the h-index
suggested in 2005 by Jorge E. Hirsch
of the University of California, San Diego
to quantify the scientific productivity of physicist
s and other scientists based on their publication record. The h-b-index developed by Michael Banks of the Max Planck Institute for Solid State Research
in Germany, takes the index further by evaluating the impact of compounds used in solid-state physics
and scientific topics in general.
The h-b-index is defined in the same manner as the h-index
, but is based on a topic (or compound) search instead of a scientists name. The h-index
defined by J. Hirsch is:
For the case of a topic it is useful to define the h-b index in terms of the number of years, n as
If the h-b index is linear with the number of years, then m is given as the gradient. In this respect, a compound or topic with a large m and h-b index can be defined as a hot topic.
Online web programs are available to directly calculate a scientist's M-number and H-index values, such as ScHolarIndex and Publish and Perish.
(WoS), (as of May 2006):
A more complete database can be found here
H-index
The h-index is an index that attempts to measure both the productivity and impact of the published work of a scientist or scholar. The index is based on the set of the scientist's most cited papers and the number of citations that they have received in other publications...
suggested in 2005 by Jorge E. Hirsch
Jorge E. Hirsch
Jorge E. Hirsch is an Argentine American professor of physics at the University of California, San Diego. He is known for his for public warnings in 2005 and 2006 about the increasing risk of nuclear war that he claimed was being caused by an unnecessarily aggressive military nuclear policy on the...
of the University of California, San Diego
University of California, San Diego
The University of California, San Diego, commonly known as UCSD or UC San Diego, is a public research university located in the La Jolla neighborhood of San Diego, California, United States...
to quantify the scientific productivity of physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...
s and other scientists based on their publication record. The h-b-index developed by Michael Banks of the Max Planck Institute for Solid State Research
Max Planck Institute for Solid State Research
The Max Planck Institute for Solid State Research is part of the Max Planck Society which operates 80 research facilities in Germany. It is a research institute located in Büsnau which is part of Stuttgart, Germany....
in Germany, takes the index further by evaluating the impact of compounds used in solid-state physics
Solid-state physics
Solid-state physics is the study of rigid matter, or solids, through methods such as quantum mechanics, crystallography, electromagnetism, and metallurgy. It is the largest branch of condensed matter physics. Solid-state physics studies how the large-scale properties of solid materials result from...
and scientific topics in general.
The h-b-index is defined in the same manner as the h-index
H-index
The h-index is an index that attempts to measure both the productivity and impact of the published work of a scientist or scholar. The index is based on the set of the scientist's most cited papers and the number of citations that they have received in other publications...
, but is based on a topic (or compound) search instead of a scientists name. The h-index
H-index
The h-index is an index that attempts to measure both the productivity and impact of the published work of a scientist or scholar. The index is based on the set of the scientist's most cited papers and the number of citations that they have received in other publications...
defined by J. Hirsch is:
-
- A scientist has index h if h of his/her Np papers have at least h citations each, and the other (Np – h) papers have at most h citations each.
For the case of a topic it is useful to define the h-b index in terms of the number of years, n as
If the h-b index is linear with the number of years, then m is given as the gradient. In this respect, a compound or topic with a large m and h-b index can be defined as a hot topic.
Online web programs are available to directly calculate a scientist's M-number and H-index values, such as ScHolarIndex and Publish and Perish.
h-b and m -indices of some topics in Physics
Based on the Science Citation Index (SCI) under the Web of ScienceWeb of Science
ISI Web of Knowledge is an academic citation indexing and search service, which is combined with web linking and provided by Thomson Reuters. Web of Knowledge coverage encompasses the sciences, social sciences, arts and humanities. It provides bibliographic content and the tools to access, analyze,...
(WoS), (as of May 2006):
- carbon nanotubeCarbon nanotubeCarbon nanotubes are allotropes of carbon with a cylindrical nanostructure. Nanotubes have been constructed with length-to-diameter ratio of up to 132,000,000:1, significantly larger than for any other material...
s: h-b = 167 m = 12.85 - Nanowires: h-b = 105 m = 8.75
- quantum dotQuantum dotA quantum dot is a portion of matter whose excitons are confined in all three spatial dimensions. Consequently, such materials have electronic properties intermediate between those of bulk semiconductors and those of discrete molecules. They were discovered at the beginning of the 1980s by Alexei...
s: h-b = 149 m = 7.84 - fullereneFullereneA fullerene is any molecule composed entirely of carbon, in the form of a hollow sphere, ellipsoid, or tube. Spherical fullerenes are also called buckyballs, and they resemble the balls used in association football. Cylindrical ones are called carbon nanotubes or buckytubes...
s: h-b = 140 m = 7.78 - giant magnetoresistanceMagnetoresistanceMagnetoresistance is the property of a material to change the value of its electrical resistance when an external magnetic field is applied to it. The effect was first discovered by William Thomson in 1856, but he was unable to lower the electrical resistance of anything by more than 5%. This...
: h-b = 116 m = 6.82 - M-theoryM-theoryIn theoretical physics, M-theory is an extension of string theory in which 11 dimensions are identified. Because the dimensionality exceeds that of superstring theories in 10 dimensions, proponents believe that the 11-dimensional theory unites all five string theories...
: h-b = 79 m = 6.58 - quantum computation: h-b = 73 m = 5.21
- TeleportationQuantum teleportationQuantum teleportation, or entanglement-assisted teleportation, is a process by which a qubit can be transmitted exactly from one location to another, without the qubit being transmitted through the intervening space...
: h-b = 61 m = 5.08 - superstrings: h-b = 99 m = 3.96
- heavy fermion: h-b = 97 m = 3.73
- Spin valveSpin valveA spin valve is a device consisting of two or more conducting magnetic materials, that alternates its electrical resistance depending on the alignment of the magnetic layers, in order to exploit the Giant Magnetoresistive effect. The magnetic layers of the device align "up" or "down" depending on...
: h-b = 48 m = 3.43 - spin glassSpin glassA spin glass is a magnet with frustrated interactions, augmented by stochastic disorder, where usually ferromagnetic and antiferromagnetic bonds are randomly distributed...
: h-b = 108 m = 3.38 - porous siliconPorous siliconPorous silicon is a form of the chemical element silicon which has introduced nanoporous holes in its microstructure, rendering a large surface to volume ratio in the order of 500 m2/cm3.-History:...
: h-b = 104 m =3.25 - Quantum Critical PointQuantum Critical PointA quantum critical point is a special class of continuous phase transition that takes place at the absolute zero of temperature, typically in a material where the phase transition temperature has been driven to zero by the application of a pressure, field or through doping.Conventional phase...
: h-b = 42 m = 2.63 - geometrical frustrationGeometrical frustrationIn condensed matter physics, the term geometrical frustration means a phenomenon in which the geometrical properties of the crystal lattice or the presence of conflicting atomic forces forbid simultaneous minimization of the interaction energies acting at a given site.This may lead to highly...
: h-b = 21 m = 2.63 - Quantum informationQuantum informationIn quantum mechanics, quantum information is physical information that is held in the "state" of a quantum system. The most popular unit of quantum information is the qubit, a two-level quantum system...
: h-b = 65 m = 2.41 - magnetoresistanceMagnetoresistanceMagnetoresistance is the property of a material to change the value of its electrical resistance when an external magnetic field is applied to it. The effect was first discovered by William Thomson in 1856, but he was unable to lower the electrical resistance of anything by more than 5%. This...
: h-b = 172 m = 2.39 - spin iceSpin iceA spin ice is a substance that is similar to water ice in that it can never be completely frozen. This is because it does not have a single minimal-energy state. A spin ice has "spin" degrees of freedom , with frustrated interactions which prevent it freezing...
: h-b = 17 m = 2.13 - perovskitePerovskiteA perovskite structure is any material with the same type of crystal structure as calcium titanium oxide , known as the perovskite structure, or XIIA2+VIB4+X2−3 with the oxygen in the face centers. Perovskites take their name from this compound, which was first discovered in the Ural mountains of...
s: h-b = 103 m = 2.10 - kondoKondo effectIn physics, the Kondo effect describes the scattering of conduction electrons in a metal due to magnetic impurities. It is a measure of how electrical resistivity changes with temperature....
AND lattice: h = 63 m = 1.97 - Spin liquid: h-b = 45 m = 1.55
- ferroelectricityFerroelectricityFerroelectricity is a property of certain materials which possess a spontaneous electric polarization that can be reversed by the application of an external electric field. The term is used in analogy to ferromagnetism, in which a material exhibits a permanent magnetic moment. Ferromagnetism was...
: h-b = 78 m = 1.39 - Spin frustration: h-b = 30 m = 1.36
- Amorphous siliconAmorphous siliconAmorphous silicon is the non-crystalline allotropic form of silicon. It can be deposited in thin films at low temperatures onto a variety of substrates, offering some unique capabilities for a variety of electronics.-Description:...
: h-b = 116 m = 1.10 - Antiferroquadrupolar: h-b = 18 m = 1.00
- Optical latticeOptical latticeAn optical lattice is formed by the interference of counter-propagating laser beams, creating a spatially periodic polarization pattern. The resulting periodic potential may trap neutral atoms via the Stark shift. Atoms are cooled and congregate in the locations of potential minima...
: h-b = 43 m = 0.90 - Spin flop: h-b = 34 m = 0.83
- pyrochlorePyrochlorePyrochlore 2Nb2O6 is a solid solution between the niobium end member , and the tantalum end member .-Occurrence:...
: h-b= 61 m = 0.62 - BorideBorideIn chemistry a boride is a chemical compound between boron and a less electronegative element, for example silicon boride . The borides are a very large group of compounds that are generally high melting and are not ionic in nature. Some borides exhibit very useful physical properties. The term...
: h-b = 46 m =0.44
A more complete database can be found here
h-b and m -indices of some compounds in Solid-state Physics
| Compound | h-b index | m |
|---|---|---|
| C-60 Fullerene A fullerene is any molecule composed entirely of carbon, in the form of a hollow sphere, ellipsoid, or tube. Spherical fullerenes are also called buckyballs, and they resemble the balls used in association football. Cylindrical ones are called carbon nanotubes or buckytubes... |
182 | 5.20 |
| GaN Gan Gan may refer to:-Computing and telecommunications:*.gan, the file extension for documents created by GanttProject*Generic Access Network formerly known as Unlicensed Mobile Access *Global Area Network- Mythology :... |
144 | 2.12 |
| SrTiO3 | 94 | 1.96 |
| CeCu2Si2 | 39 | 1.44 |
| MgB2 | 67 | 1.31 |
| Nb3Sn | 48 | 0.94 |
| Ni2MnGa | 37 | 0.82 |
| V3Si | 39 | 0.77 |
| CeB6 | 32 | 0.76 |
| Si28 | 17 | 0.31 |
General references
- "An index to quantify an individual's scientific research output," PNAS 102(46):16569-16572, November 15, 2005.
- Hirsch, Jorge E., (2005), "An index to quantify an individual's scientific research output".
- Banks, Michael G., (2006), "An extension of the Hirsch Index: Indexing scientific topics and compounds".
- "Top five in Physics", Nature May (2006).
- "Hottest topics in Physics revealed", PhysicsWeb May (2006).