| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1493860 | Optical Materials | 2015 | 4 Pages |
•Light-induced heating under CW laser light is investigated in LiNbO3-type crystals.•Two-photon excited polarons work as absorption center, generating heat source.•The accumulation effect of the polarons causes catastrophic breakdown of crystals.•The threshold intensity is estimated to be on the order of MW/cm2 for LiNbO3.
We investigate light-induced heating by nonlinear absorption in LiNbO3-type crystals under continuous-wave (CW) laser irradiation. The heat source is one-photon absorption by long-lived excited states created by two-photon absorption. The accumulated effect of excited states, which act as light absorbers, is significant for a CW laser. Light-induced heating causes catastrophic CW laser breakdown in LiNbO3-type crystals in which the band-gap energy is less than twice the photon energy and in which long-lived excited states, like polarons, can exist. For LiNbO3, the threshold intensity for catastrophic breakdown is estimated to be in the order of MW/cm2.
