Determine the durability of bonded walk-off-compensated BBO interfaces

Determine whether the bonded interfaces in walk-off-compensated BBO stacks with alternating optic-axis orientations can withstand prolonged high-power continuous-wave deep-ultraviolet exposure.

Background

The paper proposes walk-off-compensated BBO as a complementary route to improving deep-ultraviolet second-harmonic generation. A bonded stack of equal-length plates with alternating optic-axis orientations could reverse the transverse walk-off between plates, enabling a larger and more symmetric focus while maintaining nonlinear interaction length. The authors explicitly leave unresolved whether the bonded interfaces can survive prolonged high-power continuous-wave exposure at these wavelengths.

References

Such a device could permit a larger, more symmetric focus that combines high conversion efficiency with lower peak intensity and a cleaner DUV mode; the remaining question is whether the bonded interfaces withstand prolonged high-power CW DUV exposure.

— Robust watt-level continuous-wave deep-ultraviolet lasers near 230 nm  (2608.25544 - Cai et al., 26 Aug 2026) in Section 6, “Discussion and outlook”