摘要 |
A hybrid transmission-reflection grating includes an array of essentially parallel principal interfaces, with each principal interface separating a first medium and a second medium. The first medium has a first index of refraction, and the second medium has a second index of refraction. The first medium allows for transmission of quantum-mechanical objects in excess of one percent of an incident number of quantum-mechanical objects. The array of principal interfaces has a spacing distance between adjacent principal interfaces. The first medium has a width in the direction normal to the principal interfaces, the width being less than the spacing distance. Each principal interface has a length such that either (1) the length is greater that the width divided by tan(2thetac), wherein thetac is an critical angle of total external reflection for the quantum-mechanical objects at the principal interface, or (2) the length is greater that the width divided by tan(2thetac), wherein thetac is a critical angle defined by 2pi sin(thetac)sigma=lambda, with lambda being de Broglie wavelength of the quantum-mechanical objects and sigma being a roughness of the principal interface.
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