Why Does Negative Current Occur in LEDs at Low Voltage?

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SUMMARY

The discussion centers on the phenomenon of negative current in LEDs when subjected to low forward voltage. It highlights that LEDs exhibit luminescence even at negative current due to inherent leakage currents. Additionally, the I-V curves of LEDs vary by color because different colors correspond to distinct band gaps, requiring varying voltages to initiate significant conduction. The experiment involved multiple LEDs, confirming these observations across different setups.

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Superman234
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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
 
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Please show your experimental setup.

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.
 

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