A first layer, a first spacer layer, and a second layer of a semiconductor wafer can be etched to produce a plurality of columnar structures extending from the substrate layer and including a first optical cavity situated about the first gain medium, a second optical cavity situated about the second gain medium, and a first spacer region contacting the first gain medium and the second gain medium. Also, a photonic microparticle formed from a layered semiconductor wafer and of a columnar structure having a first optical cavity situated about a first gain medium, a second optical cavity situated about a second gain medium, and a first spacer region contacting the first gain medium and the second gain medium. The first optical cavity and the second optical cavity in the photonic microparticle are each capable of generating laser light with a distinct spectral peak when energetically excited.

A compound of the following structure is provided:

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A compound of the following structure is provided:

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A device for providing excitation light for analyzing a biological sample by way of fluorescence measurement is disclosed. The device includes a light emission unit configured to selectively emit first emission light via a first beam path or second emission light via a second beam path. The device also includes a filter unit designed to filter the first emission light and the second emission light in order to transmit different excitation bands of the emission light to generate the excitation light. The filter unit includes a plurality of interference filters for the excitation bands and a filter changing device to which the interference filters are attached. The filter changing device is designed to move the interference filters together and to arrange one of the interference filters in each beam path. The device further includes a deflection unit configured to combine the beam paths and direct them to an output of the device for outputting the excitation light. The deflection unit is arranged in the beam paths between the filter unit and the output.