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1. Interannual Modulation of Northern Hemisphere Winter Storm Tracks by the QBO

   https://doi.org/10.1002/2017GL076929  

   Wang, Jiabao ; Kim, Hye-Mi ; Chang, Edmund K. ( March 2018 , Geophysical Research Letters)
2. Modulation of the MJO and North Pacific Storm Track Relationship by the QBO

   https://doi.org/10.1029/2017JD027977  

   Wang, Jiabao ; Kim, Hye-Mi ; Chang, Edmund K. M. ; Son, Seok-Woo ( April 2018 , Journal of Geophysical Research: Atmospheres)
3. QBO/Solar Influences on the Tropical Madden‐Julian Oscillation: A Mechanism Based on Extratropical Wave Forcing in Late Fall and Early Winter

   https://doi.org/10.1029/2022JD037824  

   Hood, Lon L. ; Trencham, Natasha E. ; Galarneau, Thomas J. ( March 2023 , Journal of Geophysical Research: Atmospheres)

   Possible sources of the observed modulation of the tropical Madden‐Julian oscillation (MJO) by the stratospheric quasi‐biennial oscillation (QBO) and the 11‐year solar cycle are investigated using 41 years of reanalysis data and archived climate model data. Larger upward fluxes of extratropical planetary‐scale waves, leading in some cases to sudden stratospheric warmings (SSWs), are observed in late fall and early winter during the easterly phase of the QBO than during the westerly phase (the “Holton‐Tan effect”). A similar but smaller increase occurs, on average, during solar minima relative to solar maxima. In addition to the warming at high latitudes, extratropical wave forcing events produce cooling and reduced static stability in the tropical lower stratosphere. Here, it is found that if SSWs occur in early winter (before ∼mid‐January), the reduced static stability produces, on average, a statistically significant, lagged strengthening of the MJO. This therefore represents a possible mechanism for producing, or at least enhancing, the observed QBO and solar modulations of the MJO in boreal winter. An initial analysis of archived climate model data shows that at least one model version with realistic QBO and solar forcing and with 4 X CO2 forcings partly simulates both of these characteristics (QBO/solar modulation of early winter wave forcing and lagged strengthening of the MJO following early winter SSWs). However, the modeled MJO is insufficiently sensitive to QBO‐induced static stability reductions, precluding simulation of the QBO‐MJO connection. 

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4. Photo-Luminescence Modulation Circuits for Solar Cell Based Optical Communications

   https://doi.org/10.1109/ISCAS.2019.8702596  

   Leon-Salas, Walter D. ; Fan, Xiaozhe ( May 2019 , 2019 IEEE International Conference on Circuits and Systems)

   High-efficiency solar cells, such as GaAs solar cells, exhibit strong luminescent emissions in the infrared. This paper presents two circuits that are able to modulate these luminescent emissions while harvesting energy from the solar cell. These circuits can be used in Internet-of-Things applications where devices need an energy source and a means to transmit information wirelessly. The proposed circuits are based on a boost DC-DC converter and are suitable for binary (on-off) modulation. These circuits require only minimal additional hardware (either a switch or an AND gate) for their implementation. Proof-of-concept prototypes of these circuits were built and tested. Experimental results show a tradeoff between harvested energy and bit error rate. 

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5. Solar Cell Photo-Luminescence Modulation for Optical Frequency Identification Devices

   https://doi.org/10.1109/TCSI.2018.2867445  

   Leon-Salas, Walter Daniel ; Fan, Xiaozhe ( May 2019 , IEEE Transactions on Circuits and Systems I: Regular Papers)