The technology is based on two-photon absorption; when the beam of an ultrafast (for example, femtosecond) laser is tightly focused on a volume of photosensitive material, the polymerization ...

The average laser power used ranges from 3mW for small knots to 13 mW for larger ones, as measured just before the objective (note that the power in the sample is further reduced by about a factor of ...

Scientists at EPFL and IBM Research have developed a compact optical amplifier based on a photonic chip that vastly outperforms traditional optical amplifiers in both bandwidth and efficiency. This ...

Photon upconversion involves a series of non-linear optical processes where the sequential absorption of two or more photons leads to the emission of a single photon with energy greater than the sum ...