An important specification for laser diode's used in tunable diode laser absorption spectroscopy (TDLAS) is the laser's tuning coefficient. This is specified on the data sheet as picometers of change per milliamp of change in the bias current, and nanometers of change per. Whether you are pumping a Yb-doped fiber laser, driving a solid-state crystal, performing Raman spectroscopy or locking an atomic transition line like Rubidium at 780. 24 nm, your experimental success depends not just on having a laser diode, but on having one that emits at exactly the right. One of the advantages of semiconductor laser diodes compared to other laser technologies is their ability to be tuned to an adjacent wavelength. This is. laser diode (LD) are extremely dependent on the temperature of its chip. For a laser diode (LD) with high output power, it is difficult to precisely and quickly control its temperature because of the large thermal power. Variation of lasing wavelength with temperature is a key factor to determine packaging thermal resistance in laser diodes.