A linear gradient multilayer Laue lens

The tilted multilayer Laue lens (MLL) is not capable of effective focusing hard X-rays to below 10 nm. The wedged MLL has the theoretical capability to focus hard X-rays to below 1 nm with a high level of efficiency, however, it is more challenging to fabricate compared with the tilted MLL. In view of this, a novel linear gradient multilayer Laue lens in the hard X-ray region is proposed in this paper. Simulation at the energy of 12 keV reveals that the focusing performance of such MLL is better than that of the tilted MLL and close to that of the wedged MLL, it can achieve both high efficiency and small focus, meanwhile such new structure is easier to fabricate than wedged MLL.