A one-degree of freedom (DOF) tunable single fiber ring depolarizer is proposed by setting the bend-induced birefringence in the fiber ring specially to behave as a half-wave plate (HWP) and with the optimal coupling ratio of the coupler. Depolarization can be realized by just rotating the fiber ring. The methods of making and testing the HWPperformance of the fiber ring are analyzed and discussed. A 12-meter long fiber ring depolarizer is demonstrated to depolarize a Fabry-Perot (FP) laser with 10-meter coherent length. Degree of polarization (DOP) of 1.5% can be reached by rotating the whole set of fiber ring. Moreover, if a polarizer ahead of the fiber ring is inserted, a full scale one degree of freedom tunable depolarizer can be realized.
In this report, p-type macroporous silicon has been prepared by anodization. A phosphorus diffusion step is employed for
the formation of three dimensional pn junction structures on this macroporous silicon. I-V and C-V measurement were
employed to characterize the electrical properties. The results were compared with numeric simulation with T-SUPREM4
and MEDICI. It has been demonstrated that three-dimensional structure can increase the effective junction
area and the collective efficiency remarkably, and hence improve the performance of semiconductor radiation detector.