Efficient dual-wavelength diode-end-pumped laser with a diffusion-bonded Nd:YVO_4/Nd:GdVO_4 crystal

Abstract

A new type of diffusion-bonded Nd:YVO 4 /Nd:GdVO 4 heterocomposite crystal is originally designed and applied to diode-end-pumped laser for achieving an efficient dual-comb picosecond operation with selfmode locking for the first time. As high as 1.1 W of the total average output power at 1063.18 and 1064.37 nm is generated under an incident pump power of 5.1 W. The corresponding mode-locked pulse width is 42 ps at a pulse repetition rate of 3.82 GHz. Through the optical beating between two carrier frequencies of each spectral component, a train of ultrashort pulses with sub-terahertz repetition rate is further generated with the effective duration of down to 1.6 ps.

Dual-wavelength Nd:YVO laser with c-cut crystal geometry

“…In this case, the laser host should possess distinct emission peaks. This situation can be found in vanadate laser crystals such as Nd:YVO, Nd:GdVO and Nd:GdYVO [41][42][43][44][45] and is shown in figure 1. The Nd:YVO crystals are well-known for high laser efficiency and large absorption and stimulated emission crosssections at 1064.1 nm for laser polarization parallel to the optical axis (E//π) [44][45][46].…”

“…The later enables one to generate pairs with separation smaller than the offered FSR [17,18,39,40]. Two laser crystal geometry can be also employed provided that the emission peaks are close to each other [41,42].…”

Red-diode-pumped Cr:Nd:GSGG laser: two-color mode-locked operation

“…In particular, two-color mode-locked laser operation has been attracting a great deal of attention due to potential usage of such lasers in application like generation of coherent terahertz waves and formation of ultrahigh pulse repetition rates by optical beating. Simultaneous dual/tri-wavelength mode-locked laser operation with picosecond pulses has been shown in many Nd-based laser gain media, including Nd:LYSO [18], Nd:SYSO [19], Nd:LGGG [20][21][22], Nd:CNGG [23], Nd:CLTGG [24], Nd:GdVO 4 [25], Nd:YVO 4 ∕Nd:GdVO 4 [26][27][28], Nd:GAGG [29], Nd:YVO 4 ∕ Nd:LuVO 4 [30], Nd:YVO 4 ∕Nd:KGW [30], Nd:YSAG [31], Nd:YAG [32,33], Nd:YAP [34], and Nd:Gd:SrF 2 [35]. In these works, operating in a multiwavelength regime was established using different techniques such as usage of disordered multicenter crystals with inhomogeneously broadened emission spectrum [22], and/or operating with cavity mirrors with specially designed reflectivity properties [33], enrolling two different laser crystals in the cavity [26][27][28], employment of intracavity etalons [34], and by cooling the laser crystal to cryogenic temperatures [32].…”