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In electron microscope the electron can be accelerated to higher energy to obtain a finer resolution. It can resolve on the scale of molecules but can barely perceive the atoms.

To resolve at atomic and sub-atomic level we need to go to particle accelerators. Particle Accelerators are gargantuan machines which can be regarded as giant microscopes for probing into the innermost recesses of matter - an awesome complement to the giant telescopes which probe to the edges of the Universe .

To arrive at the resolving power of particle accelerator we must know Special Theory of Relativity and we must make relativistic corrections in order to arrive at the correct resolving power of the particle accelerators. These are described in the Appendix XXXXIV . Here we will just use them to arrive at the resolving power of the particle accelerators.

Relativistic momentum is related to the total energy E by the following relation ship:


de Broglie wavelength associated with this particle is:


Using Equation (1.99), the resolving power of various particle accelerators operational around the world is tabulated in Table(1.13).[Taken from Table(9.1), “Overview of Particle Physics”, by Abdus Salam, New Physics, edited by Paul Davies, Cambridge University Press, 1992]

Table 1.13. The resolution of the particle accelerators around the World.

Name&Location Energy reached Year Resolution Particle detected
Rutherford*Manchester,UK. Alpha decay10MeV,alpha particle’s velocity= 2×10 7 m/s, Alpha particle=4He nucleus; 1911 4.5×10^ -15 m Nucleus size= 10^ -14 m; Rutherford determined the size to be 30fmBut the correct estimate is 7fm;
1919 1.24×10^ -15 m Protonssize= 10^ -15 m=1fm;
1932 1.24×10^ -15 m Neutronssize= 10^ -15 m =1fm
1GeV 1.24×10^ -15 m
Bepc(e + e - ) Beijing 4GeV 1987
TRISTAN(e + e - ) Japan 60GeV 1987
10GeV 1979 1.24×10^ -16 m Quarks size= 10^ -16 m
SLC(e + e - ) Stanford,California,USA; 100GeV 1987 1.24×10^ -17 m W - , W + &Z 0 detected
LEP(I) (e + e - ) Large electron-positron collidorCERN, Geneva; 100GeV 1987 1.24×10^ -17 m
LEP(II) (e + e - ) CERN,Geneva 200GeV 1995 6.2×10^ -18 m Top Quarksdetected
HERA(ep)Hamburg 320GeV 1991 3.87×10^ -18 m
SpSCERN, Geneva 900GeV 1986 1.38×10^ -18 m
TevatronFermiLab,USA 1TeV 1987 1.24×10^ -18 m No excited state of quarks or leptons detected size= 10^ -18 m
TevatronFermiLab,USA 2TeV 1987 6.2×10^ -19 m
UNKSerpukhov,Russia 3TeV 1995 4.13×10^ -19 m
EeSerpukhov,Russia 4TeV ? 3×10^ -19 m
Large HadronCollider(LHC),CERN,Geneva 16TeV ? 7.75×10^ -20 m
SSC(super particle superconductingCollider),USA; 40TeV ? 3.1×10^ -20 m
1PeV ? 1.24×10^ -21 m
1EeV ? 1.24×10^ -24 m

* the first particle accelerator was established at Cavendish Laboratory, Cambridge University. In 1919 Rutherford became the first Director and he was instrumental in establishing the particle accelerator.

In Metal the wavelength is comparable to the lattice constant. This is like light falling through a narrow aperture whose dimension is comparable to the wavelength. Incident light will form a circular diffraction pattern behind the aperture on the target screen. This implies that conducting electron in a metallic lattice is strongly scattered by the lattice centers. Hence it has a very low mobility.

In Semiconductor, the de Broglie wave length is much larger than the lattice constant. Hence lattice scattering is weak and only the gross imperfections cause the scattering. These gross imperfections could be phonons and dislocations extending over several lattice constants. This is what makes conducting electrons much more mobile in semiconductor as compared to that in metal.

In metal, conducting electrons behave like degenerate gas and not quite like ideal gas whereas in semiconductors they behave like non-degenerate gas which is more like ideal gas obeying ideal gas law.

In ideal gas the molecules are far apart, independent of one another and possessing average energy of (3/2)kT whereas in degenerate gas the molecules are closely packed and average kinetic energy is much larger than (3/2)kT. In Table(1.14),

Metals and Semiconductors parameters have been tabulated in the same table.

Table(1.14). Conductivity(σ), Fermi Level(E F ), Mean Free Path(L*) and Mean Free Time(τ) at 0°C for monovalent metals and semiconductors.

Metal σ (10 6 S/cm) ρ(Ω-cm) n (10^ 22 / cm 3 ) μ e cm^ 2 / (V-s)= σ/(nq) E F (eV) L*(A°) τ(fs)= m e μ/q ×10^ -4
Li 0.12 8.3 ×10^ -6 4.62 16.2 4.7 110 9
Na 0.23 4.35 ×10^ -6 2.65 54.17 3.1 350 31
K 0.19 5.26 ×10^ -6 2.1 370 44
Cu 0.64 1.67 ×10^ -6 8.5 47 7.0 420 27
Ag 0.68 1.47 ×10^ -6 5.9 72 5.5 570 41
Ge 47 n i = 2.25 ×10^ 13 3900 2106 2217
Si 300k n i = 1.15 ×10^ 10 1350 729 767.6
GaAs 70.5M n i =2 ×10^6 8600 4645.5 4890

Questions & Answers

how can chip be made from sand
Eke Reply
is this allso about nanoscale material
are nano particles real
Missy Reply
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
where is the latest information on a no technology how can I find it
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
has a lot of application modern world
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Solid state physics and devices-the harbinger of third wave of civilization. OpenStax CNX. Sep 15, 2014 Download for free at http://legacy.cnx.org/content/col11170/1.89
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