FALLSEM2013 14 CP3001 02 Aug 2013 RM01 Int BioTechFall2013QuantumPhys

8/13/2019 FALLSEM2013 14 CP3001 02 Aug 2013 RM01 Int BioTechFall2013QuantumPhys

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Physics for BioTechnology

Course Code: PHYSICSL T P C

3 0 0 3

Lecture3 per week

Theory

Total 5 Units

Unit 1, Unit 2, Unit 3, Unit 4, Unit 5

Unit 1: Quantum PhysicsUnit 2: Laser

Unit 3: Fiber Optics and UltraSonicsUnit 4: Radiation PhysicsUnit 5: Thermodynamicsand NanoTechnology


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Unit 1: Quantum Physics

1. Dual nature of electron magnetic radiation

2. de Broglie wavesCompton effect experimental verification

3. Heisenberg uncertainty principle

4. Schrodinger equation - application

5. Application of Quantum Mechanics - Scanning TunnelingMicroscope

6. Atomic Force Microscope.


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Unit 2: Laser

1. Laser Characteristics

2. Absorption, Spontaneous emission, stimulated emission

3. Pumping Mechanism

4. Population Inversion

5. 3 level, 4 level laser

6. Types Ruby laser, He-Ne laser

7. Biological application


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Unit 3: Fibre Optics and Ultrasonics

1. Light propagation through fibers

2. Acceptance angle numerical aperture

3. Types of Fibres

4. Step Index, grade Index

5. Applications - Endoscope

6. Properties of Ultrasonic

7. Generation- Magnetostriction method, piezo electric method

8. Detection

9. Applications


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Unit 4: Radiation Physics

1. Types of Nuclear radiations

2. Units of radiation

3. Labeling techniques

4. Computerized tomography

5. Principles of NMR: T1 and T2 relaxation, Chemical shift

6. Principles of MRI


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Unit 5: Thermodynamics and nanotechnology

1. Laws of Thermodynamics

2. Concepts of entropy, enthalpy, free energy

3. Nanomaterials

4. Properties of Nanomaterials

5. Applications of Nanotechnology in Biology and Medicine


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EVALUATION1. Internal evaluation: Marks 502. External Evaluation: Marks 50

Internal evaluationContinuous Assessment TestCat 1: Marks 15, CAT 2: Marks 153 Quizzes : 3 X 5 = 15 Marks1 Assignment : 5 Marks

Theory:

TOTAL : 50

Term End Exam (TEE)

External Evaluation: Marks 50

Total : Marks 100


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Max Planck (18581947) Niels Bohr (18851962)


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Max Born (18821970)

Werner Heisenberg (19011976)


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Erwin Schrdinger (18871961)Willard Gibbs (18391903)


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Paul Dirac (19021984)

All of quantum theory can be resumed intwo sentences.In nature, actions smaller than = 1.1

1034 Js are not observed.All intrinsic properties in naturewiththe exception of masssuch as electric

charge, spin, parities, etc., appear as

integer numbers; in composed systems

they either add or multiply.


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Newtons Physics

Light as Particles

Interference diffraction

Wave nature (A , )

Electromagnetic Radiation

BLACK BODY RADIATION ???

Max Planck 1900

Quantization of EMR

EINSTEIN (1905)

Energy ----- Discrete bundles or Quanta


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All of quantum theory can be resumed in two sentences.In nature, actions smaller than = 1.1 1034 Js are not

observed.

All intrinsic properties in naturewith the exception ofmasssuch as electric charge, spin, parities, etc., appear

as integer numbers;

in composed systems they either add or multiply.


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If it moves, it is made of quantons, or quantumparticles.

In nature, all intrinsic propertieswith the exceptionof masssuch as

electric charge, spin, parities, etc., appear as integer

numbers.

Since all physical systems are made of quantons, in

composed systems intrinsic properties either add or

multiply


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DUAL NATURE OF ELECTRO MAGNETIC RADIATIONS

What is the wavelength (or wavevector k = 2/)

to be used to compute the phase

= kx for particles?

An EM wave of energy E carries momentum p

p = E/c in the direction of the wave vectork = 2/


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A photon of frequency has energy E = h

and carries momentump = E/c = h = h/ = h/2 . 2 / = k

E = h = energy of a photon

p = h/ = k momentum of a photon

For light, the classical path no longer exists for distance scales d ~

Or d . p ~ h.

CRITERION THAT IDENTIFIES BORDER BETWEEN CLASSICALAND QUANTUM PHENOMENA.

Plancks Einstein Equation


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A famous quantum effect: how do trainwindows manage to show twosuperimposedimages?


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PARTICLE WAVE

ELECTROMAGNETIC WAVE

QUANTISED

C =2.988 x 1010

cm/sVacuum

= c

Radiowaves

MicrowavesIRVisibleUVXRayGamma


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Is light particle or waves ?


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PHOTO ELECTRIC EFFECT

EPhoton= hv

hv = hvo + KEmax

Threshold energy hvo(Work Function)


Einstein 1905

Conservation of Energy requires


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Scanning tunneling spectroscopy(STS) is an experimental

technique which uses a scanning tunneling microscopeScanning tunneling microscope

A scanning tunneling microscope is a powerful instrument for

imaging surfaces at the atomic level. Its development in 1981

earned its inventors, Gerd Binnig and Heinrich Rohrer , the

Nobel Prize in Physics in 1986. For an STM, good resolution

is considered to be 0.1 nm lateral resolution and...

(STM) to probe the local density of electronic states (LDOS)

and band gapof surfaces and materials on surfaces at the

atomic scale
http://www.absoluteastronomy.com/topics/Scanning_tunneling_microscopehttp://www.absoluteastronomy.com/topics/Band_gaphttp://www.absoluteastronomy.com/topics/Band_gaphttp://www.absoluteastronomy.com/topics/Scanning_tunneling_microscope


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Scanning tunneling microscopy (STM) is the highestresolution imaging and nanofabrication technique available

It relies on quantum tunneling of electrons from asharp metal tip to a conducting surface


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STS involves observation of changes in constant-current

topographs with tip-sample bias, local measurement of the

tunneling current versus tip-sample bias (I-V) curve,

measurement of the tunneling conductance

Since the tunneling current in a scanning tunneling

microscope only flows in a region with diameter ~5, STS is

unusual in comparison with other surface

spectroscopytechniques, which average over a larger

surface region.
http://www.absoluteastronomy.com/topics/Spectroscopyhttp://www.absoluteastronomy.com/topics/Spectroscopy


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While STS can provide spectroscopic information with amazing

spatial resolution, there are some limitations.The STM and STS lack chemical sensitivity.

Since the tip-sample bias range in tunneling experiments is limited to

where is the apparent barrier height, STM and STS are only sample

valence electron states.

Element-specific information is generally impossible to extract from

STM and STS experiments, since the chemical bond formation

greatly perturbs the valence states.

LIMITATIONS


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An STM image of a monolayer, 2-dimensional liquid crystalof 1-octadecanoic acid (stearic acid) on a substrate ofhighly oriented pyrolytic graphite (HOPG). The individualmethylene groups are clearly visible, and the molecularstructure of stearic acid can be identified


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ATOMIC FORCE MICROSCOPY (AFM)


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ATOMIC FORCE MICROSCOPY (AFM)

Atomic force microscopy (AFM) is a powerful technique

for investigating surfaces.

In the imaging mode, a sharp tip is scanned over a

surface and some surface parameter monitored.

Traditionally, the deflection of a cantilever holding the tip

is monitored by a photodiode.When the tip scans across the surface, it will interact

with the latter, and deflect according to the interaction:

if there is an attractive interactionbetween the surface

and the tip, the tip will be deflected towards the surface,

whereas deflection away from the surface will occur in

the case of a repulsive tip-surface interaction.


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AFM could be called simply a high-resolution surfaceprofiler if not one important difference

AFM cantilever is so thin and sensitive that it can sense

the minute surface forces, Van-der-Waals forces,

magnetic forces, electrostatic forces, etc.

It allows to use AFM to investigate not only surface

topography, but probe surface physical, chemical, and

magnetic properties.


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The main components of this tool are thin cantileverwithextremely sharp (10 A to 100 A in radius) probing tip,

a 3D piezo-electric scanner,and optical systemto measure deflection of the cantilever.When the tip is brought into the contact with the surface orin its proximity, or is tapping the surface, it being affectedby a combination of the surface forces (attractive and

repulsive).Those forces cause cantilever bending and torsion, whichis continuously measures via. the deflection of thereflected laser beam.3D scanner moves the sample or, in alternative designs,the cantilever, in 3 dimensions thus scanning

predetermined area of the surface.A vertical resolution of this tool is extremely high reaching0.1 A(1 A is on the order of atomic radius).


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The deflection is kept constant through a feed-back loop, andthe z-movement of the stage needed for accomplishing thismonitored.

The technique has many advantages, including capability ofextremely high resolution (atomic in favourable cases), noneed for sample treatment or coating, no need for vacuum,

and possibility for quantitative measurements of sample form,distribution and roughness over a range of magnifications.


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Freshly cleaved mica was attached to a standard microscope slideby double-sided adhesive and mounted.

The mica was imaged in contact mode using standard 450um long,single arm, etched silicon probes. Shown is a deflection imagetaken at a scan rate of 24.4Hz with integral gain set to 0.665 andproportional gain set to 0.176.


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Protein/DNA complex imaged in air. The protein is a restrictionendonuclease (Eco RI) bound to plasmid DNA. The ability of the

AFM to image DNA/protein complexes rapidly and without fixationmakes it an extremely useful tool for numerous investigations.1.2um scan.


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Magnetic domains in low-coercivity, amorphous CoZrNb film usedin emerging, high-Ms thin-film heads. 50um scan.

Cross-tie domains, and the effects of edge roughness.


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.

Revealing the hidden atom in graphite with AFMshowing all atoms within the hexagonal graphite unitcells. Image size 22 nm2.

FALLSEM2013 14 CP3001 02 Aug 2013 RM01 Int BioTechFall2013QuantumPhys

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