Ultra-high Power Reduction in Modulated VCSEL for Lasing
The paper reports on an experimental investigation of influence of the current modulation on the properties of a vertical-cavity surface-emitting laser (VCSEL) when modulated with a square wave signal. In terms of lasing below the static threshold current, the output power response as a function of modulation frequency and amplitude is measured for an 850 nm VCSEL. We demonstrated that the current modulation frequency and amplitude play an important role in reducing power consumption of VCSEL for lasing. Power consumption is significantly reduced to about > 60% in response to the both current modulation frequency and amplitude. The light-Current curve linearity of the VCSEL for different modulation signal is also investigated. The results demonstrated that the harmonic distortion is highly depends on the amplitude of input signal, high distortion occur at large signal amplitude. An operating the VCSEL devices at low power is very desirable, as lower power level consumption offer lower thermal effects which essential for higher speed modulation bandwidth.