Search

Your search keyword '"Ronningen, T. J."' showing total 34 results
Start Over Author "Ronningen, T. J."
34 results on '"Ronningen, T. J."'

3. Ionization coefficients and excess noise characteristics of AlInAsSb on an InP substrate

Author

Ronningen, T. J., primary, Kodati, S. H., additional, Jin, X., additional, Lee, S., additional, Jung, H., additional, Tao, X., additional, Lewis, H. I. J., additional, Schwartz, M., additional, Gajowski, N., additional, Martyniuk, P., additional, Guo, B., additional, Jones, A. H., additional, Campbell, J. C., additional, Grein, C., additional, David, J. P. R., additional, and Krishna, S., additional

Published
2023
Full Text
View/download PDF

7. High gain, low noise 1550 nm GaAsSb/AlGaAsSb avalanche photodiodes

Author

Lee, S., primary, Jin, X., additional, Jung, H., additional, Lewis, H., additional, Liu, Y., additional, Guo, B., additional, Kodati, S. H., additional, Schwartz, M., additional, Grein, C., additional, Ronningen, T. J., additional, David, J. P. R., additional, Campbell, Joe. C., additional, and Krishna, S., additional

Published
2023
Full Text
View/download PDF

8. Suppressing leakage current by interfacial engineering for highly sensitive, broadband, self-powered FACsPbI3 perovskite photodetectors.

Author

Bhardwaj, Bhupesh, Bothra, Urvashi, Singh, Shivam, Mills, Sophie, Ronningen, T. J., Krishna, Sanjay, and Kabra, Dinesh

Subjects
STRAY currents, PHOTODETECTORS, PEROVSKITE, ELECTRON transport, ENGINEERING, CESIUM isotopes, INTERFACIAL friction
Abstract

Dark current is considered as one of the important parameters to suppress temporal noise and enhance sensitivity of photodetectors. This study shows the effect of active layer thickness and different interfacial layers in the suppression of leakage current. High-sensitivity (D* > 1012 Jones) perovskite photodetectors (PPDs) are fabricated using the device structure of ITO/PEDOT: PSS/FA0.95Cs0.05PbI3 (dPVSK)/ electron transport layer (ETL)/BCP/Ag with noise current <1 pA Hz−½. These PPDs have a broadband response from near-ultraviolet to near-infrared region (300–840 nm). The overall performance of the PPDs enhanced for the optimal thickness of active layer of dPVSK = 600 nm and ETL PC60BM layer thickness of dETL = 50 nm. The total noise current of the PPD is further suppressed by replacing the ETL PC60BM (in = 63.11 fA Hz−½) layer by a PC70BM (in = 33.41 fA Hz−½) layer. This further improved other figures of merit for these PPDs. Comparison with published reports on PPDs is included to compare with the state-of-the-art detectors. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

13. Optical constants of Al0.85Ga0.15As0.56Sb0.44 and Al0.79In0.21As0.74Sb0.26

Author

Guo, B., primary, Jones, A. H., additional, Lee, S., additional, Kodati, S. H., additional, Liang, B., additional, Xue, X., additional, Pfiester, N. A., additional, Schwartz, M., additional, Winslow, M., additional, Grein, C. H., additional, Ronningen, T. J., additional, Krishna, S., additional, and Campbell, J. C., additional

Published
2021
Full Text
View/download PDF

15. AlInAsSb avalanche photodiodes on InP substrates

Author

Kodati, S. H., primary, Lee, S., additional, Guo, B., additional, Jones, A. H., additional, Schwartz, M., additional, Winslow, M., additional, Pfiester, N. A., additional, Grein, C. H., additional, Ronningen, T. J., additional, Campbell, J. C., additional, and Krishna, S., additional

Published
2021
Full Text
View/download PDF

17. Open-circuit voltage photodetector architecture for infrared imagers

Author

Specht, T. R., primary, Duran, J. M., additional, Taghipour, Z., additional, Fragasse, R., additional, Tantawy, R., additional, Ronningen, T. J., additional, Ariyawansa, G., additional, Reyner, C., additional, Smith, D. S., additional, Fuller, E., additional, Khalil, W., additional, and Krishna, S., additional

Published
2020
Full Text
View/download PDF

21. Optical constants of Al0.85Ga0.15As0.56Sb0.44 and Al0.79In0.21As0.74Sb0.26.

Author

Guo, B., Jones, A. H., Lee, S., Kodati, S. H., Liang, B., Xue, X., Pfiester, N. A., Schwartz, M., Winslow, M., Grein, C. H., Ronningen, T. J., Krishna, S., and Campbell, J. C.

Subjects
AVALANCHE photodiodes, OPTICAL materials, QUANTUM efficiency, ABSORPTION coefficients, SPLINES, OPTICAL constants
Abstract

Digital alloy Al0.85Ga0.15As0.56Sb0.44 and random alloy Al0.79In0.21As0.74Sb0.26 avalanche photodiodes with a 1-μm multiplication layer exhibit low excess noise under 543-nm laser illumination comparable to Si avalanche photodiodes. This has motivated a study of the optical characteristics of these materials. The absorption coefficients and complex refractive indices were extracted via variable-angle spectroscopic ellipsometry. Features of three semiconductor layer fitting approaches are compared, and a Kramers–Kronig-consistent basis spline function was chosen due to its flexibility and accuracy of approximating optical constants of quaternary materials. The external quantum efficiency has been calculated based on the extracted absorption coefficients and is shown to agree well with the measured external quantum efficiency. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

30. From the Chair.

Author

Ronningen, T. J.

Subjects
LGBTQ+ people, AWARD winners, AWARD presentations
Abstract

The article titled "From the Chair" discusses the mission of Out to Innovate, which is to recognize and celebrate the accomplishments of LGBTQ+ individuals in STEM. The article highlights the three new Recognition Award winners and the American Chemical Society's special issue on LGBTQ+ Trailblazers. The author encourages readers to attend the online awards ceremony and mentions the upcoming Pride month. The article also provides information on volunteer opportunities within the organization and invites members to apply to join the Board of Directors. The application process and expectations for board members are outlined, and contact information is provided for further inquiries. [Extracted from the article]

Published
2022

32. Engineering of impact ionization characteristics in In0.53Ga0.47As/Al0.48In0.52As superlattice avalanche photodiodes on InP substrate.

Author

Lee, S., Winslow, M., Grein, C. H., Kodati, S. H., Jones, A. H., Fink, D. R., Das, P, Hayat, M. M., Ronningen, T. J., Campbell, J. C., and Krishna, S.

Subjects
SUPERLATTICES, AVALANCHE photodiodes, IMPACT ionization, CHROMIUM-cobalt-nickel-molybdenum alloys, THRESHOLD energy
Abstract

We report on engineering impact ionization characteristics of In0.53Ga0.47As/Al0.48In0.52As superlattice avalanche photodiodes (InGaAs/AlInAs SL APDs) on InP substrate to design and demonstrate an APD with low k-value. We design InGaAs/AlInAs SL APDs with three different SL periods (4 ML, 6 ML, and 8 ML) to achieve the same composition as Al0.4Ga0.07In0.53As quaternary random alloy (RA). The simulated results of an RA and the three SLs predict that the SLs have lower k-values than the RA because the electrons can readily reach their threshold energy for impact ionization while the holes experience the multiple valence minibands scattering. The shorter period of SL shows the lower k-value. To support the theoretical prediction, the designed 6 ML and 8 ML SLs are experimentally demonstrated. The 8 ML SL shows k-value of 0.22, which is lower than the k-value of the RA. The 6 ML SL exhibits even lower k-value than the 8 ML SL, indicating that the shorter period of the SL, the lower k-value as predicted. This work is a theoretical modeling and experimental demonstration of engineering avalanche characteristics in InGaAs/AlInAs SLs and would assist one to design the SLs with improved performance for various SWIR APD application. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

34. Optical constants of Al0.85Ga0.15As0.56Sb0.44 and Al0.79In0.21As0.74Sb0.26.

Author

Guo, B., Jones, A. H., Lee, S., Kodati, S. H., Liang, B., Xue, X., Pfiester, N. A., Schwartz, M., Winslow, M., Grein, C. H., Ronningen, T. J., Krishna, S., and Campbell, J. C.

Subjects
*AVALANCHE photodiodes, *OPTICAL materials, *QUANTUM efficiency, *ABSORPTION coefficients, *SPLINES, *OPTICAL constants
Abstract

Digital alloy Al0.85Ga0.15As0.56Sb0.44 and random alloy Al0.79In0.21As0.74Sb0.26 avalanche photodiodes with a 1-μm multiplication layer exhibit low excess noise under 543-nm laser illumination comparable to Si avalanche photodiodes. This has motivated a study of the optical characteristics of these materials. The absorption coefficients and complex refractive indices were extracted via variable-angle spectroscopic ellipsometry. Features of three semiconductor layer fitting approaches are compared, and a Kramers–Kronig-consistent basis spline function was chosen due to its flexibility and accuracy of approximating optical constants of quaternary materials. The external quantum efficiency has been calculated based on the extracted absorption coefficients and is shown to agree well with the measured external quantum efficiency. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results