Negative resistance refers to a behavior in circuits where current increases as voltage decreases, contrasting with Ohm's law. A tunnel diode, a heavily doped p-n junction diode, exemplifies this phenomenon by demonstrating a decrease in electric current with an increase in voltage, and is primarily used for fast switching in computers and high-frequency oscillators. The tunnel diode operates based on quantum mechanics principles, particularly the tunneling effect, and was invented by Leo Esaki in 1958.

1. Al-amin
Department of Electrical & Electronic Engineering
Jatiya Kab Kazi Nazrul Islam University, Trishal, Mymensingh,
Banglade
Negative Resistances
What is tunnel diode?

2. Negative Resistances is a
behavior in which the current and
voltage are inversely proportional
to each other.
A normal circuit with a resistor
following ohm's law has a current
drop, when the voltage
decreases.
R = V / I
Or, V = I*R
In case of a negative resistance,
the current increases with a
voltage drop.
Practically, there is nothing as a
negative resistor. Its just behavior
on the V-I graph, where there is a
negative slope, and operating in
that region would give you a
behavior of negative resistance.
Negative Resistances

3. What is tunnel diode?
A Tunnel diode is a heavily doped p-n junction diode in which the electric
current decreases as the voltage increases.
In tunnel diode, electric current is caused by “Tunneling”. The tunnel diode
is used as a very fast switching device in computers. It is also used in high-
frequency oscillators and amplifiers
Tunnel diode was invented in 1958 by Leo Esaki
A tunnel diode is also known as Esaki diode which is named after Leo Esaki for his
work on the tunneling effect. The operation of tunnel diode depends on the quantum
mechanics principle known as “Tunneling”. In electronics, tunneling means a direct
flow of electrons across the small depletion region from n-side conduction band into
the p-side valence band

4. This Photo by Unknown Author is licensed under CC BY-NC-ND