Output power enhancement of a self-frequency-doubled laser by selective excitation of inequivalent active centers in La_2CaB_10O_19 (Nd:LCB) crystal

We demonstrated the output power enhancement of a self-frequency-doubled laser with Nd3+-doped lanthanum calcium borate La2CaB10O19 (Nd:LCB) crystals by selective excitation of its inequivalent active centers. When the Nd3+ ions located in the Ca2+ sites were excited in the Nd:LCB crystal, the fundamental laser at the wavelength of 1066 nm was successfully realized, which can keep the self-frequency-doubled wavelength away from the self-absorption peak of Nd3+ ions at about 523 nm. By optimizing the key parameters, the maximum output power of 801 mW was achieved with the frequency-doubling at the wavelength of 533 nm, and the enhancement of output power was about 7.8 times compared with the results by excitation of Nd3+ ions in the La3+ sites. Up to now, this output power of the self-frequency-doubled laser represents the highest one in the Nd:LCB crystal, and the efficient emission at 533 nm should have promising applications in the visible range, such as laser displays, optical data storage, laser printing, etc. Meanwhile, the selective excitation of inequivalent active ions and the enhancement of the self-frequency-doubled laser may provide some inspiration for the investigation of multi-functional materials.