title: High-order diffraction suppression using modulated groove position gratings.
abstract: Conventional diffraction gratings composed of a series of equally spaced slits suffer from wavelength overlapping caused by high-order diffraction. Here modulated groove position gratings (MGPGs) are proposed to significantly suppress the high diffraction orders. Both numerical solution and experimental results demonstrate the effectiveness of MGPGs. The suppression ratio is determined by the number of grating grooves used. By using an MGPG with 10,000 grooves, a suppression ratio as high as 18,000 can be obtained. In addition, the minimum linewidth is kept to 1/4 of the grating period, which enables grating realization with high line density employing today's nanofabrication technology. Our results should be of great interest in both diffraction grating theory and applications, particularly due to MGPGs' applicability in a wide wavelength range and realizability with high line density.
authors: Key Laboratory of Microelectronics Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029, China.
authors: Nan
authors: N
authors: Gao
authors: Changqing
authors: C
authors: Xie