A tunnel diode is a specialized semiconductor device with a unique negative resistance characteristic, allowing it to switch between states rapidly. It operates based on the principle of quantum tunneling, where electrons can pass through energy barriers even when classically forbidden. The tunnel diode symbol consists of two terminals connected by a curved line with an inward arrow, representing the forward biasing direction. This unique diode is often used in high-frequency oscillators, amplifiers, and microwave applications, where its fast switching capabilities and ability to operate at high frequencies make it a valuable component in specific electronic circuits.
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The figure below displays Tunnel Diode Symbol.