Hall effect presentation

1. By –
Group G4
Guided by –
Prof. Binay Kumar
Prof. Sorav Sur
By –
Group G4
Keshav,Twinkle,Pradyumn,
Komal,Bhoomika
Guided by –
Prof. Binay Kumar
Prof. Sourav Sur

2. The modern theory of electromagnetism was systematized by Maxwell in the
paper "On Physical Lines of Force", which was published in four parts between
1861–1862. While Maxwell's paper established a solid mathematical basis for
electromagnetic theory, the detailed mechanisms of the theory were still being
explored. One such question was about the details of the interaction between
magnets and electric current, including whether magnetic fields interacted with
the conductors or the electric current itself. In 1879 Edwin Hall was exploring this
interaction, and discovered the Hall effect while he was working on his doctoral
degree at Johns Hopkins University in Baltimore, Maryland. Eighteen years
before the electron was discovered, his measurements of the tiny effect produced
in the apparatus he used were an experimental tour de force, published under the
name "On a New Action of the Magnet on Electric Currents“.
Edwin Hall

3. AIM
1. To determine the Hall
voltage developed across
the sample material.
2. To calculate the Hall
coefficient and the carrier
concentration of the sample
material.

5. Hall effect setup

7. Constant current power supply

8. Hall effect Probes
• Measure magnetic field
• Magnetic field is directly proportional
to current
• Commonly called hall sensor
• Can measure both sign and
amplitude

9. Electromagnets
ELECTROMAGNETS
An electromagnet is a type of magnet in which the magnetic field is produced by an electric
current. Electromagnets usually consist of wire wound into a coil. A current through the wire
creates a magnetic field which is concentrated in the hole, denoting the centre of the coil. The
magnetic field disappears when the current is turned off. The wire turns are often wound around
a magnetic core made from a ferromagnetic or ferrimagnetic material such as iron; the magnetic
core concentrates the magnetic flux and makes a more powerful magnet.
The main advantage of an electromagnet over a permanent magnet is that the magnetic field can
be quickly changed by controlling the amount of electric current in the winding. However, unlike a
permanent magnet that needs no power, an electromagnet requires a continuous supply of current
to maintain the magnetic field

10. Examples of Electromagnets

11. Digital Gauss Meter
 The Gaussmeter operates on the principle of Hall Effect in
semiconductors. A semiconductor material carrying
current develops an electro-motive force, when placed in
a magnetic field, in a direction perpendicular to the
direction of both electric current and magnetic field. The
magnitude of this e.m.f. is proportional to the field
intensity if the current is kept constant, this e.m.f. is
called the Hall Voltage. This small Hall Voltage is
amplified through a high stability amplifier so that a
millivoltmeter connected at the output of the amplifier
can be calibrated directly in magnetic field unit (gauss).

12. Digital Gauss Meter

13. THEORY

14. Hall effect
It is the production of
a potential difference
(maximum) across the
ends of an electrical
conductor when a
magnetic field is
applied in a direction
perpendicular to that
of flow of current.

15. I
e
B
v
B
F
m
v
F
m
w
t

16. e
e
e
e
e
e
e
e
Eh
e
F
e
Fm
Saturated state -> Final value of hall voltage

17. At saturated state,
F
e
Fm
=
q Eh
= q v B
Eh
= v B
I = n q A v
v = I / n q A
Vh
Eh
= w
Vh
= v Bw
Vh
=(I B w)/(n q A)
Vh
=
(I B w)/(n q w t)
Vh
= (I B)/(n q t)
Vh
= (I B)/(t)
Rh
×
Vh
=
Rh
× t
I × B
=
Rh
1
n q

19. FORMULA
USED

20. n = 1 / RHq
Where,
Rh is hall coefficient of the
material,
Vh is the hall voltage developed
across the ends of the
conductor,
t is the thickness of the
conductor,
I is the current flowing through
the conductor,
Where,
n is the number density of
carriers or the carrier
concentration,
Rh is hall coefficient of the
material,
q is the charge of an
electron

21. Procedure And simulation:
• I am going to explain the procedure in two parts :
1. Simulation on virtual lab:
2. Procedure we did in real lab :
So lets see how to perform the experiment after going
through so much of theory 🙈👉👉

22. Simulation on virtual lab:
 Controls:
 select procedure : this is used to select the part of the experiment to perform
1. Magnetic field Vs current
2. Hall effect setup
 Select material : This slider activate only if hall effect setup is selected and this is used to
select the material for finding hall cofficient and carrier concentration
Buttons:
1) Insert probe/remove probe: This button is used to insert/remove the probe in between
the solenoid
1) Show voltage/current : This will activate only if Hall effect selected and it is used to display
the hall voltage /current in the digital meter
1) Reset : This button is used to repeat the experiment

23. Procedure for doing the simulation :
 To measure the magnetic field generated
in the solenoid and to plot a graph between
current flowing through the solenoid and
the magnetic field:
1. Select magnetic fieldVs current from the procedure combo
box.
2. Click the insert probe button then place the probe in
between the electromagnet by clicking the wooden stand in
the simulator.
3. Using current slider, we vary current slightly and noted magnetic field
corresponding to different current from gauss meter And Graph is
plotted b/w I (x axis) and M(Y axis) Which is a straight line .

24. Hall effect procedure:
1. Select hall effect setup from the combo box then insert the
probe in between the electromagnet by clicking on the wooden
stand.
2. Now for plotting the graph between hall voltage and
magnetic field , keep the hall current at a constant value and
vary the current passing through solenoid slowly and
corresponding to it note down the value of hall voltage and
magnetic filed.
3. Now keeping the solenoidial current Constant , Set the hall
current slider value to minimum and then vary the hall
current using the slider and note down the corresponding hall
voltage by clicking on “show voltage” button
4. Then plot the curve between hall voltage and hall current
and find the slope of the curve.
5. Then by using the equation
(Rh*B/t )=slope ;
(B = magnetic field ,t =thickness of the material )
calculate the hall cofficient and the carrier concentration

25. Procedure for doing in real lab:
 Connect constant current source to the solenoid/electromagnet
 Gauss probe is connected to the gauss meter and placed at the middle of the two
solenoid. Then switch on the gauss meter and constant current source.
 Vary the current through the solenoid from 1 A to 5 A and note the corresponding gauss
meter readings
 Switch off the gauss meter and constant current source and turn the knob of constant
current source towards the minimum current
 Fix the hall probe on a wooden stand and. Connect the green wires to constant current
generator and the red wires to mili voltmeter in the hall effect aapratus
 Replace the hall probe With four probe and place the sample material at the middle of
the two electromagnets and adjust their gap to a minimum so that the poles do not
touch the probe
 Switch on the constant current source and carefully increase the current I and measure
the corresponding Hall voltage Vh. Repeat this for different magnetic field .And plot the
graph between the hall current and hall voltage.
 Thickness t of the material is used using screw gauge and then hall cofficient is
calculated using the equation (Rh*B)/t= slope

26. Critical Analysis
1) The hall probe must be perpendicular to the
magnetic field.
2) Magneto-resistance
3) The length of the hall probe should be nearly
three times its width.
4) The current should not be too large to cause
heating effect.

27. TABULATIONS

28. 7
4
0.5929
S. No. Current flowing through the
solenoid
(in mA)
Magnetic field
generated
(in T)
1 1 0.1482
2 1.5 0.2223
3 2 0.2964
4 2.5 0.3706
5 3 0.4447
6 3.5 0.5188
7 4 0.5929
8
9
4.5
5
0.6670
0.7411
9 5 0.7411

29. S.
No.
Magnetic field
generated by the
solenoid
(in T)
Thickness
of the
probe
(in mm)
Hall
current
(in mA)
Hall voltage
(in mV)
1 0.1482 0.2 1 14.378
2 0.1482 0.2 1.5 21.567
3 0.1482 0.2 2 28.756
4 0.1482 0.2 2.5 35.945
5 0.1482 0.2 3 43.133
6 0.1482 0.2 3.5 50.322
7 0.1482 0.2 4 57.511

30. GRAPHS

31. Magnetic field vs Current Graph

33. Hall Voltage vs Hall current graph

34. CALCULATION

36. ERROR
ANALYSIS

37. 0.02862

39. RESULT – Hall Coefficient

40. RESULT – Carrier concentration

41. Conclusion
By performing this experiment, we were able to find the
hall coefficient and the carrier concentration of the given
Germanium probe whose values came out to be,
and,
respectively.

42. QUANTUM HALL EFFECT
The quantum Hall effect (or integer quantum Hall effect) is a quantized version of the Hall
effect, observed in two-dimensional electron systems subjected to low temperatures and
strong magnetic fields, in which the Hall resistance Rxy exhibits steps that take on the
quantized values at certain level.
where VHall is the Hall voltage, Ichannel is the channel current, e is the elementary
charge and h is Planck's constant. The divisor ν can take on either integer (ν = 1, 2, 3,...) or
fractional (ν = 1/3, 2/5, 3/7, 2/3, 3/5, 1/5, 2/9, 3/13, 5/2, 12/5,...) values.The quantum Hall
effect is referred to as the integer or fractional quantum Hall effect depending on whether ν is
an integer or fraction, respectively.

44. The Nobel Prize in
Physics 1985 was
awarded to Klaus
von Klitzing "for the
discovery of the
Quantized Hall
effect”

46. Applications Of Hall Effect in Daily life
 Speed detection
 Current sensing application
 Used as Magnetometers to measure magnetic field
 Magnetic position sensing in brushless DC motors
 Automotive fuel level indicator

47. Speed detection
These sensors
are composed
of a hall
Element and a
permanent
magnet near a
toothed disc
attached on
the rotating
shaft.

48. Current Sensor
 When
Current
flow
through a
conductor,a
magnetic
field is
created.

49. Manetometers
Smartphones are
equipped with
magnetic
compass.
These
magnetometer
are sensors
based on hall
effect.

50. Electric Motor Control
 Some types of brushless
DC electric motors use
hall effect sensors to
detect the position of
the rotor and feed that
information to the motor
controller.This allows for
more precise motor
control.

51. Automotive Fuel Level Indicator
 The fuel level is
indicated and
displayed by
proper signal
condition of
Hall voltage.

52. OBSERVATIONS, GRAPHS AND CALCULATIONS
BY: TWINKLE DAHIYA

53. TWINKLE DAHIYA

54. TWINKLE DAHIYA

55. TWINKLE DAHIYA

56. TWINKLE DAHIYA

57. TWINKLE DAHIYA

58. TWINKLE DAHIYA

59. TWINKLE DAHIYA

60. TWINKLE DAHIYA

61. TWINKLE DAHIYA

62. TWINKLE DAHIYA

63. TWINKLE DAHIYA

64. TWINKLE DAHIYA

65. TWINKLE DAHIYA

66. TWINKLE DAHIYA
SOME OTHER INFORMATION:
 Recently, researchers have replicated the Hall Effect, using radio waves (photons) instead of
electric current (electrons). This technique could be used to create advanced communication
systems that boost signal transmission in one direction while simultaneously absorbing signals
going in the opposite direction.
 We can also use the concept of Hall Coefficient Inversion to find out the ratio of carrier
concentration in case of a lightly doped semiconductor.

67. 1. Observation Table
2. Graphs
3. Calculations
4. Error Analysis
5. Result
presented By – KOMAL
(group-4)

68. Observation table :

69. GRAPHS : 1
.

70. GRAPH : 2

71. GRAPH : 3

72. C
A
L
C
U
L
A
T
I
O

73. Error Analysis :

74. RESULT

75. GRAPHS ANDCALCULATION
-:PRADYUMN

76. S.
No.
Current flowing
through the
electromagnets
(in A)
Magnetic field
generated
(in T)
1 1 0.1482
2 1.5 0.2223
3 2 0.2964
4 2.5 0.3706
5 3 0.4447
6 3.5 0.5188
7 4 0.5929
8 4.5 0.6670

78. S.
No.
Magnetic
field
generated by
electromagne
ts (in T)
Thicknes
s of the
probe
(in m)
Hall
current
(in mA)
Hall
voltage
(in mV)
1 0.4447 0.0001 1 86.26
2 0.4447 0.0001 1.5 129.40
3 0.4447 0.0001 2 172.53
4 0.4447 0.0001 2.5 215.66
5 0.4447 0.0001 3 258.80
6 0.4447 0.0001 3.5 301.93
7 0.4447 0.0001 4 345.06

80. CALCULATION

81. Observations:
( BY BHOOMIKA)
Table 1: magnetic field vs current :

82. TABLE2:
We fix the current as 5 ampere,
So, magnetic field will be 0.7411 G as constant magnetic
field.
And, thickness of the material is taken as 0.0003 metre.

84. CALCULATIONS:

85. ERROR ANALYSIS :

86. Results:
 The Hall coefficient for the Germanium
sample was found to be (1.94+0.07)*10-2
m3/C, and the number of carriers was
found to be 3.22*1020+0.12*1020 /m3.