Biomedical subjects

P B Phua

Publications and source records attributed to P B Phua.

2 recordsLinked to original sources

PubMed2006

Coherent polarization locking with near-perfect combining efficiency.

We demonstrate the coherent locking of two orthogonal polarized lasers by using polarization selective loss. The two orthogonal polarizations are locked coherently to produce a resultant polarization state that sees minimal cavity loss. In contrast to the Michelson locking schemes, our scheme has the advantage of easy tunability, which helps to routinely achieve near-perfect (>99%) combining efficiency even when the power of the two arms is highly imbalanced and is varied from a power ratio of unity to >5. We also demonstrate an interesting phenomenon in which a miniscule injection of an antiphase field component from one arm into another can significantly inhibit the locking mechanism.

Journal Article↗

PubMed2006

High-average-power mid-infrared ZnGeP2 optical parametric oscillator with a wavelength-dependent polarization rotator.

A wavelength-dependent polarization rotator is used to transform the orthogonal polarizations of the signal and idler of a near-degenerate type II KTP optical parametric oscillator (OPO) into a common polarization state. This common polarization allows a single ZnGeP2 OPO to fully utilize the 2 microm signal and idler KTP OPO outputs in a mid-IR conversion. The simple design of the wavelength-dependent polarization rotator yields a compact source that simultaneously generates four mid-JR wavelengths collinearly with a total mid-IR average power of 5.5 W at a >15 kHz pulse repetition rate.

Journal Article↗