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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:

………………………………………………………………1.98

de Broglie wavelength associated with this particle is:

……………………………………………………………1.99

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

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
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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