| 1. |
- Adolfsson, Göran, 1981, et al.
(author)
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Realization of spectrally engineered semiconductor Fabry-Perot lasers with narrow geometrical tolerances
- 2011
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In: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 109:9, s. 093112-
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Journal article (peer-reviewed)abstract
- Spectrally engineered semiconductor Fabry-Perot laser resonators are designed to enhance the optical feedback for selected longitudinal modes, which thereby require less gain for lasing. This is achieved by introducing refractive index perturbations along the length of the resonator. However,the physical realization of these resonators is a challenge because of very narrow tolerances; in particular the need for precise positioning of the end facets of the resonator in relation to the perturbations, and the excess propagation loss associated with the perturbations, has been a majorconcern. We report on a method to achieve high-quality end facet mirrors enabling precise positioning relative to the perturbations, the latter which are realized as lateral corrugations of the waveguide. Measurements show that the mirror quality is comparable to that of cleaved mirrorsand that the additional loss introduced by the perturbations adds
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| 2. |
- Adolfsson, Göran, 1981, et al.
(author)
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Spectral engineering of semiconductor Fabry–Perot laser cavities in the weakly and strongly perturbed regimes
- 2010
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In: Journal of the Optical Society of America B: Optical Physics. - 1520-8540 .- 0740-3224. ; 27:1, s. 118-127
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Journal article (peer-reviewed)abstract
- By inserting index perturbations at certain positions along a semiconductor Fabry–Perot laser cavity thethreshold gain for one or several of the longitudinal cavity modes can be selectively lowered to facilitate, e.g.,single-mode or two-color operation. Previous design methods were limited to a fairly small number of perturbations,leading to only weakly perturbed cavities and thus a limited freedom in tailoring the spectral propertiesof the laser. In our approach we fully account for all multiple-reflection events and use a search spacethat permits any distribution of the locations and lengths of the perturbations. We are therefore able to designcavities with almost arbitrary spectral properties with very low threshold gain values for, e.g., the lasingmodes of a two-color cavity. Constraining the design by reducing the geometrical freedom, which can be used toincrease the smallest feature size to simplify fabrication, we seamlessly approach the weakly perturbed regimewhile maintaining much of the freedom for spectral engineering.
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| 3. |
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| 4. |
- Frigyesi, Ildiko, et al.
(author)
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Robust isolation of malignant plasma cells in multiple myeloma.
- 2014
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In: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 123:9, s. 1336-1340
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Journal article (peer-reviewed)abstract
- Molecular characterization of malignant plasma cells is increasingly important for diagnostic and therapeutic stratification in multiple myeloma (MM). However, the malignant plasma cells represent a relatively small subset of bone marrow cells, and need to be enriched prior to analysis. Currently, the cell surface marker CD138 (SDC1) is used for this enrichment, but has an important limitation in that its expression decreases rapidly after sampling. Seeking alternatives to CD138, we performed a computational screen for myeloma plasma cell markers and evaluated seven candidates systematically. Our results conclusively show that the markers CD319 (SLAMF7/CS1) and CD269 (TNFRSF17/BCMA) are considerably more robust than CD138, and enable isolation of myeloma plasma cells under more diverse conditions, including in samples that have been delayed or frozen. Our results form the basis of improved procedures for characterizing cases of multiple myeloma in clinical practice.
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