High-contrast photoluminescent patterns in lithium fluoride crystals produced by soft x-rays from a laser-plasma source

Abstract

A technique using soft x-rays and extreme ultraviolet light generated by a laser-plasma source has been investigated for producing low-dimensionality photoluminescent patterns based on active color centers in lithium fluoride (LiF) crystals. Strong visible photoluminescence at room temperature has been observed in LiF crystals from fluorescent patterns obtained by masking the incoming radiation. This technique is able to produce colored patterns with high spatial resolution on large areas and in short exposure times as compared with other coloration methods.

IR‐SNOM on lithium fluoride films with regular arrays based on colour centres

“…Quite recently [5] an innovative irradiation technique, using EUV radiation or soft X-rays by a laser plasma source, has been shown to be an efficient tool to create optically active CCs in LiF crystals. In such crystals, a coloured pattern with high spatial resolution on large areas was produced and detected through a strong visible photoluminescence emitted at room temperature.…”

Infrared near-field microscopy with the Vanderbilt free electron laser: overview and perspectives

“…The creation of defects--called ''color centers'' [27] because of their influence on the color of the crystal--is a critical step in the corresponding fabrication procedure [28][29][30][31]. Such defects can be created by different processes; in the present case, we explored the results of an innovative irradiation technique [31] based on extreme ultraviolet (EUV) radiation and soft X-rays emitted by a laser plasma-point source. This approach can produce patterned coloration on large areas.…”

Luminescent nanostructures based on colour centres produced in LiF films by direct writing with an X‐ray microprobe

“…Recently LiF films treated by low energy electrons have been successfully exploited for the realisation of miniaturised active devices [7], like optical microcavities and point-light sources. The search for fabrication methods and processing techniques allowing the realization of light emitting structures for novel photonic applications, prompt us to use soft X-rays from different sources for LiF films [8] and crystals [9] irradiation, obtaining the efficient formation of stable CCs. Up to now, only electron [10] and ion [11] microprobes have been used for direct patterning of coloured schemes in LiF.…”