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Band-to-band photoluminescence (PL) imaging is one of the experimental techniques widely used to assess non-radiative recombination rates at a fixed incident light intensity. Minority carrier lifetimes in semiconductors such as mc-Si are also affected by optical injection levels. These can be measured by transient photoconductance (TPC). In this paper, PL imaging of shunts and TPC lifetime results for incident intensities of up to 50 Suns are compared for multiple samples of mc-Si.
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Temperature sensing via photoluminescence lifetimes of Rhodamine B*
Non-invasive temperature probes have use in many settings where conventional thermometers may not be suitable or as efficient. An optical temperature probe is a material whose optical properties, such as photoluminescence (PL) or PL lifetime, are known as a function of temperature. We present results of PL lifetime studies of the organic dye Rhodamine B, which is a good candidate for use in temperature probes due to its large PL emission. We have measured PL lifetimes using time correlated single photon counting (TCSPC). The lifetimes were measured from temperatures of 15 K to 330 K. The lifetimes appear to be non-monotonic: they increase with temperature to a point, then decrease again. It is uncertain what is causing this unexpected trend, and we are in the process of verifying these lifetime measurements as well as studying other possible luminescent materials such as semiconductor quantum dots for application as temperature probes. *Research was performed at BYU as part of the NSF REU program, grant no. 1757998.
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- Award ID(s):
- 1757998
- PAR ID:
- 10106053
- Date Published:
- Journal Name:
- Bulletin of the American Physical Society
- Volume:
- 64
- Issue:
- 2
- ISSN:
- 0003-0503
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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