The pumping current of the semiconductor lasers

AI Thread Summary
The discussion centers on the possibility of negative pumping current in semiconductor lasers, specifically DFB and FP-LD lasers. The original poster is conducting numerical modeling involving rate equations and is curious about the implications of modulating bias current with a high frequency. They inquire whether the alternating current component can exceed the direct current component significantly. Participants seek clarification on the concept of negative pumping and its practical applications in laser operation. The conversation highlights the complexities of laser dynamics and the need for further experimental insights.
galq
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Hi all,

I have a question and ask for a discussion. Can the pumping current of the semiconductor lasers such as DFB laser and FP-LD, be smaller than zero?

Best Regards,
Jason.galq
 
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galq said:
Hi all,

I have a question and ask for a discussion. Can the pumping current of the semiconductor lasers such as DFB laser and FP-LD, be smaller than zero?

Best Regards,
Jason.galq

Welcome to the PF.

What do you mean? By less than zero you mean negative? Do you have some reference links you can post to help us understand your question?
 
Thanks for your reply. Yes, I mean negative pumping, but within a very small time (0.05ns). Acturally i am doing some numerical modelling and playing the rate equations. The pumping is a source term in the equation. And if we modulate the bias current, which is I_total = I0 + Delta_I * sin(2.0*pi *fm *t), where I0 is the DC part and Delta_I is the A.C. part, fm is the modulation frequency. If fm is very large (20 GHz), can the Delta_I be 3 times the I0 ? I am not familiar with the experiment at all, thus I post this question here for discussion.
 
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