V.
1
U
m
ap
Arulmigu Meenakshi Amman college of Engineering
at
hy
Vadamavandal-604410.
,P
ro
f./
Prepared by,
M
ec
h.
V.Umapathy,
Prof./Mech.
Imortant Questions and Answers
PH25C03- Applied Physics(CSIE)-II
Syllabus
1. Magnetic Materials: Parameters, Ferromagnetic materials, Ferrites - Soft and Hard
magnetic materials – GMR sensors - magnetic disk memories – Principle of magnetic
recording – Magnetic data storage.
2. Logic Gates: Conversion of Binary to decimal - decimal to binary – binary coded decimal
code-logic gates (OR, AND, NOT, NAND and NOR)–Exclusive OR gate simplification
based on basic Boolean theorems (sum of products, product of sums expression)-
simplification by Karnaugh Map method (don’t care conditions).
3. Nano-Devices: Introduction – electron density in bulk material – size dependence of Fermi
energy-quantum confinement – quantum structures: quantum wells, wires and dots – band
gap of nanomaterials. Tunneling- Coulomb blockade - single electron transistor - resonant-
tunneling diode- Carbon nanotubes: Properties and applications.
4. Quantum Computing: Quantum system for information processing - quantum states –
classical bits – quantum bits or qubits – Bloch sphere -CNOT gate – Single and multiple
qubits – quantum gates (Pauli – X, Y and Z Gates, Hadamard Gate, Phase gate - T
gate .CNOT Gate) – advantage of quantum computing over classical computing.
S.No Description
.
Unit-I
Magnetic Materials
Introduction
Introduction
- Materials affected by magnetic fields
- Used in data storage, sensors, motors
, V.
2
U
m
ap
_Parameters
at
hy
1. Permeability (μ)
,P
Magnetization ease
ro
2. Susceptibility (χ)
f./
Response to field
M
ec
3. Coercivity (Hc)
h.
Demagnetization resistance
4. Retentivity (Br)
Remanent magnetization
Types
1. Ferromagnetic
Strongly magnetic
Fe, Ni, Co
2. Ferrites
Ceramic magnets
Soft (transformers), hard (permanent)
Soft Magnetic Materials
1. Low coercivity
Easy magnetization
2. High permeability
Transformers, inductors
3. Examples
Si-Fe, Ni-Fe alloys
Hard Magnetic Materials
1. High coercivity
Resist demagnetization
2. High retentivity
Permanent magnets
3. Examples
NdFeB, SmCo
GMR Sensors
1. Giant Magnetoresistance
Resistance changes with field
2. Used in
Hard drives, sensors
, V.
3
U
m
ap
_Magnetic Data Storage_
at
hy
1. Hard disk drives
,P
Magnetic recording
ro
2. Tape storage
f./
Data archiving
M
ec
h.
Principle of Magnetic Recording
1. Magnetization
Data → magnetic field
2. Storage
Medium retains field
3. Readback
Field detection
Basic Concepts
Magnetic Parameters
1. Permeability (μ)
How easily magnetized
2. Coercivity (Hc)
Resistance to demagnetization
3. Retentivity (Br)
Magnetization remaining
Ferromagnetic Materials
1. Strong magnetism
Fe, Ni, Co, alloys
2. Domains
Aligned magnetic moments
Ferrites
1. Ceramic magnetic materials
2. Soft ferrites
Transformers, inductors
3. Hard ferrites
Permanent magnets
Soft Magnetic Materials
1. Low coercivity
Easy to magnetize
2. High permeability
Efficient
, V.
4
U
m
ap
3. Examples
at
hy
Si-Fe alloys
,P
ro
Hard Magnetic Materials
f./
1. High coercivity
M
ec
Hard to demagnetize
h.
2. High retentivity
Permanent magnets
3. Examples
NdFeB, SmCo
GMR Sensors
. Giant Magnetoresistance
Resistance changes with field
2. Used in
Hard drives, sensors
Magnetic Recording
1. Principle
Magnetize → store data
2. Hard disk drives
Data storage
3. Tape storage
Archiving
Two Marks QA
1. What are ferromagnetic materials?
Materials strongly attracted to magnets (Fe, Ni, Co)
2. Define coercivity.
Resistance to demagnetization
3. What are soft magnetic materials?
Low coercivity, easy to magnetize (Si-Fe alloys)
4. Give examples of hard magnetic materials.
NdFeB, SmCo
5. What is GMR?
Giant Magnetoresistance (used in sensors)
1
U
m
ap
Arulmigu Meenakshi Amman college of Engineering
at
hy
Vadamavandal-604410.
,P
ro
f./
Prepared by,
M
ec
h.
V.Umapathy,
Prof./Mech.
Imortant Questions and Answers
PH25C03- Applied Physics(CSIE)-II
Syllabus
1. Magnetic Materials: Parameters, Ferromagnetic materials, Ferrites - Soft and Hard
magnetic materials – GMR sensors - magnetic disk memories – Principle of magnetic
recording – Magnetic data storage.
2. Logic Gates: Conversion of Binary to decimal - decimal to binary – binary coded decimal
code-logic gates (OR, AND, NOT, NAND and NOR)–Exclusive OR gate simplification
based on basic Boolean theorems (sum of products, product of sums expression)-
simplification by Karnaugh Map method (don’t care conditions).
3. Nano-Devices: Introduction – electron density in bulk material – size dependence of Fermi
energy-quantum confinement – quantum structures: quantum wells, wires and dots – band
gap of nanomaterials. Tunneling- Coulomb blockade - single electron transistor - resonant-
tunneling diode- Carbon nanotubes: Properties and applications.
4. Quantum Computing: Quantum system for information processing - quantum states –
classical bits – quantum bits or qubits – Bloch sphere -CNOT gate – Single and multiple
qubits – quantum gates (Pauli – X, Y and Z Gates, Hadamard Gate, Phase gate - T
gate .CNOT Gate) – advantage of quantum computing over classical computing.
S.No Description
.
Unit-I
Magnetic Materials
Introduction
Introduction
- Materials affected by magnetic fields
- Used in data storage, sensors, motors
, V.
2
U
m
ap
_Parameters
at
hy
1. Permeability (μ)
,P
Magnetization ease
ro
2. Susceptibility (χ)
f./
Response to field
M
ec
3. Coercivity (Hc)
h.
Demagnetization resistance
4. Retentivity (Br)
Remanent magnetization
Types
1. Ferromagnetic
Strongly magnetic
Fe, Ni, Co
2. Ferrites
Ceramic magnets
Soft (transformers), hard (permanent)
Soft Magnetic Materials
1. Low coercivity
Easy magnetization
2. High permeability
Transformers, inductors
3. Examples
Si-Fe, Ni-Fe alloys
Hard Magnetic Materials
1. High coercivity
Resist demagnetization
2. High retentivity
Permanent magnets
3. Examples
NdFeB, SmCo
GMR Sensors
1. Giant Magnetoresistance
Resistance changes with field
2. Used in
Hard drives, sensors
, V.
3
U
m
ap
_Magnetic Data Storage_
at
hy
1. Hard disk drives
,P
Magnetic recording
ro
2. Tape storage
f./
Data archiving
M
ec
h.
Principle of Magnetic Recording
1. Magnetization
Data → magnetic field
2. Storage
Medium retains field
3. Readback
Field detection
Basic Concepts
Magnetic Parameters
1. Permeability (μ)
How easily magnetized
2. Coercivity (Hc)
Resistance to demagnetization
3. Retentivity (Br)
Magnetization remaining
Ferromagnetic Materials
1. Strong magnetism
Fe, Ni, Co, alloys
2. Domains
Aligned magnetic moments
Ferrites
1. Ceramic magnetic materials
2. Soft ferrites
Transformers, inductors
3. Hard ferrites
Permanent magnets
Soft Magnetic Materials
1. Low coercivity
Easy to magnetize
2. High permeability
Efficient
, V.
4
U
m
ap
3. Examples
at
hy
Si-Fe alloys
,P
ro
Hard Magnetic Materials
f./
1. High coercivity
M
ec
Hard to demagnetize
h.
2. High retentivity
Permanent magnets
3. Examples
NdFeB, SmCo
GMR Sensors
. Giant Magnetoresistance
Resistance changes with field
2. Used in
Hard drives, sensors
Magnetic Recording
1. Principle
Magnetize → store data
2. Hard disk drives
Data storage
3. Tape storage
Archiving
Two Marks QA
1. What are ferromagnetic materials?
Materials strongly attracted to magnets (Fe, Ni, Co)
2. Define coercivity.
Resistance to demagnetization
3. What are soft magnetic materials?
Low coercivity, easy to magnetize (Si-Fe alloys)
4. Give examples of hard magnetic materials.
NdFeB, SmCo
5. What is GMR?
Giant Magnetoresistance (used in sensors)
