Polarization splitting of optical resonant modes ina−Si:H/a−SiOx:

Abstract

We present experimental and theoretical results on polarization splitting of optical resonant modes in a-Si:H/a-SiO(x):H microcavities. It is shown experimentally that the splitting sign and value can be controlled by varying the active layer thickness. The polarization splitting achieved in the microcavities is about 8 meV owing to a large optical contrast, which is the ratio of film refractive indices in the distributed Bragg reflectors. The experimental data and theoretical analysis show that the polarization splitting may be zero at a certain angle of incidence of light determined by the microcavity parameters. The measured and calculated resonant frequency values for TM and TE polarizations were used to find the optical thickness of the active layer and the stop-band center frequency of the Bragg reflector. The account of the active layer thickness fluctuations along the lateral direction provides a better fit between the experimental and theoretical spectra.

Сферический распределенный брэгговский отражатель на основе a-Si-=SUB=-1-x-=/SUB=-C-=SUB=-x-=/SUB=- : H и a-SiO-=SUB=-2-=/SUB=-

“…Толщины рассчитывались из интерференционных картин в спектрах отражения. В дальнейшем толщины слоев, осаждае-мых на микросферу, контролировались методом in situ интерферомет-рии [14] в процессе их нанесения, исходя из сопоставления со скоростью роста и толщинами планарных слоев, осаждаемых на расположенную на горизонтальном электроде кварцевую пластинку.…”

“…Во всех исследованных спектрах наблюдалась широкая полоса отражения, которая, как и в планарных распределенных брэгговских отражателях [11,12,[14][15][16][17][18], возникает за счет брэгговского отражения от группы слоев с периодически меняющимся показателем преломле-ния. Спектральное положение центра полосы брэгговского отражения незначительно смещается при регистрации отражения в разных точках поверхности СРБО.…”

Resonant diffusive reflection of light from rough interfaces of Bragg structures (photonic crystals)

“…Actually, available work on disordered photonic crystals, e.g. [6][7][8][9][10] , concern a onedimensional randomization of the crystal along its axis, in which case the transverse disorder effects leading to the side scattering of light are completely excluded.…”

“…The model under study is applicable to the photonic crystals whose representatives are prepared by layer-by-layer growth of one-dimensional dielectric Bragg structures 9,[11][12][13] . Some qualitative sequences from this model are expected to be useful for threedimensional opal-like photonic crystals as well 8,12,[14][15][16] .…”

Polarization mode splitting in monolithic polymer microcavities

“…The most of organic semiconductors generally show broadened spectra, because of the presence of vibronic progressions and the high degree of structural disorder, however Rabi splitting ͑up to 400 meV at room temperature͒ has been reported on vertical microcavities based on conjugated polymers. 10 Moreover, polarization-induced mode splitting has been recently observed in microcavities exploiting inorganic active media, such as InGaAs quantum dots 11 and wells, 12 and hydrogenated amorphous Si, 13 and very few works have shown a similar effect on polymers. 14 Due to the relevant interest of microcavities for high-efficient light emitting diodes and vertical-cavity surface-emitting lasers, the development of novel architectures exhibiting polarization splitting has great importance for the realization of polarized optoelectronic devices.…”