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Diffraction and Gratings|2 Article(s)
Optically induced atomic lattice with tunable near-field and far-field diffraction patterns
Feng Wen, Huapeng Ye, Xun Zhang, Wei Wang, Shuoke Li, Hongxing Wang, Yanpeng Zhang, and Cheng-wei Qiu
Conventional periodic structures usually have nontunable refractive indices and thus lead to immutable photonic bandgaps. A periodic structure created in an ultracold atoms ensemble by externally controlled light can overcome this disadvantage and enable lots of promising applications. Here, two novel types of optically induced square lattices, i.e., the amplitude and phase lattices, are proposed in an ultracold atoms ensemble by interfering four ordinary plane waves under different parameter conditions. We demonstrate that in the far-field regime, the atomic amplitude lattice with high transmissivity behaves similarly to an ideal pure sinusoidal amplitude lattice, whereas the atomic phase lattices capable of producing phase excursion across a weak probe beam along with high transmissivity remains equally ideal. Moreover, we identify that the quality of Talbot imaging about a phase lattice is greatly improved when compared with an amplitude lattice. Such an atomic lattice could find applications in all-optical switching at the few photons level and paves the way for imaging ultracold atoms or molecules both in the near-field and in the far-field with a nondestructive and lensless approach. Conventional periodic structures usually have nontunable refractive indices and thus lead to immutable photonic bandgaps. A periodic structure created in an ultracold atoms ensemble by externally controlled light can overcome this disadvantage and enable lots of promising applications. Here, two novel types of optically induced square lattices, i.e., the amplitude and phase lattices, are proposed in an ultracold atoms ensemble by interfering four ordinary plane waves under different parameter conditions. We demonstrate that in the far-field regime, the atomic amplitude lattice with high transmissivity behaves similarly to an ideal pure sinusoidal amplitude lattice, whereas the atomic phase lattices capable of producing phase excursion across a weak probe beam along with high transmissivity remains equally ideal. Moreover, we identify that the quality of Talbot imaging about a phase lattice is greatly improved when compared with an amplitude lattice. Such an atomic lattice could find applications in all-optical switching at the few photons level and paves the way for imaging ultracold atoms or molecules both in the near-field and in the far-field with a nondestructive and lensless approach.
Photonics Research
- Publication Date: Oct. 04, 2017
- Vol. 5, Issue 6, 06000676 (2017)
Laser-induced controllable chirped-pitch circular surface-relief diffraction gratings on AZO glass
James Leibold, and Ribal Georges Sabat
Chirped-pitch nanoscale circular surface-relief diffraction gratings were photoinscribed on thin films of a Disperse Red 1 functionalized material using a holographic technique. A truncated conical mirror splits and redirects a converging or diverging laser beam, resulting in an interference pattern of concentric circles with a chirped pitch that can be controlled by varying the wavefront curvature. The resulting circular gratings have a diameter of 12mm and have the advantage of being produced in a fast, single-step procedure with no requirement for a master grating, photomask, or milling equipment. Chirped-pitch nanoscale circular surface-relief diffraction gratings were photoinscribed on thin films of a Disperse Red 1 functionalized material using a holographic technique. A truncated conical mirror splits and redirects a converging or diverging laser beam, resulting in an interference pattern of concentric circles with a chirped pitch that can be controlled by varying the wavefront curvature. The resulting circular gratings have a diameter of 12mm and have the advantage of being produced in a fast, single-step procedure with no requirement for a master grating, photomask, or milling equipment.
Photonics Research
- Publication Date: Jun. 12, 2015
- Vol. 3, Issue 4, 04000158 (2015)
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