# Exploring LED: Negative Current, Luminescence & I-V Curves

• Superman234
In summary, the conversation discusses the presence of negative current in an LED at low voltage and the resulting luminescence in forward voltage. The questions also inquire about the variation of I-V curves in LEDs of different colors and the reason for this difference. The individual asking the questions conducted an experiment with 5 LEDs, but still has some unexplained results. The speaker also mentions that all electronic objects have some leakage current in the same direction as the potential difference.

#### Superman234

Hi,
Why is there negative current in an LED at low voltage(set up in forward voltage)?
Why is there luminescence of an LED at negative current as described above(when LED is in forward voltage)?
How would the I-V curves of LEDs of different colours vary? Why?

The questions I've asked all resulted from an experiment that I did. and yes, I did the experiment several times with 5 LED's and still had some unexplained things...

Thanks

LEDs (and all other electronic objects) always have some leakage current, in the same direction as the potential difference.

How would the I-V curves of LEDs of different colours vary? Why?
Different colors need different voltages to start conducting (significant currents), as different colors correspond to different band gaps.

## 1. What is LED and how does it work?

LED stands for Light Emitting Diode, which is a semiconductor device that emits light when an electric current passes through it. It works by converting electrical energy into light energy through a process called electroluminescence.

## 2. What is negative current in LED?

Negative current in LED refers to the phenomenon where the LED emits light when the direction of current flow is reversed. This is known as reverse-biased operation and is the result of the charge carriers in the LED being able to recombine and emit light even in the absence of a forward bias voltage.

## 3. What is luminescence in LED?

Luminescence in LED refers to the emission of light from the LED when an electric current is passed through it. This process is caused by the recombination of electrons and holes in the semiconductor material, resulting in the release of photons in the form of light.

## 4. What is an I-V curve in LED?

An I-V curve in LED is a graphical representation of the relationship between the current (I) and voltage (V) applied to the LED. It shows the different operating regions of the LED, such as forward and reverse bias, and helps to determine the electrical characteristics of the LED, such as its voltage and current ratings.

## 5. How is LED technology being improved through the study of negative current and luminescence?

The study of negative current and luminescence in LED is helping scientists to better understand the underlying mechanisms of LED operation and to improve the efficiency and performance of LED technology. By studying these phenomena, researchers can develop new materials and designs that can lead to more efficient and durable LEDs for various applications in lighting, displays, and other electronic devices.