What type of diode can conduct in reverse bias and is often used in voltage regulation?

A Zener diode is specifically designed to conduct current in reverse bias while maintaining a constant voltage level, which makes it ideal for voltage regulation. When the voltage across a Zener diode exceeds its specified breakdown voltage, it enters the breakdown region, allowing current to flow in the reverse direction without being damaged. This characteristic enables it to stabilize voltage levels in a circuit, making Zener diodes essential components in power supply systems and voltage regulation circuits.

In contrast, rectifier diodes are primarily used for converting alternating current (AC) to direct current (DC) and are not designed to operate effectively in reverse breakdown conditions. Schottky diodes are known for their fast switching speeds and low forward voltage drop but do not have the same voltage regulation properties as Zener diodes. Light Emitting Diodes (LEDs), while capable of emitting light when forward biased, do not conduct in reverse bias to provide voltage regulation either. Thus, the Zener diode is the only option suitable for functioning as a voltage regulator by utilizing its unique reverse-bias conduction characteristics.