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1. Piezoaxionic effect

   https://doi.org/10.1103/PhysRevD.109.072009  

   Arvanitaki, Asimina; Madden, Amalia; Van_Tilburg, Ken (April 2024, Physical Review D)

   Axion dark matter (DM) constitutes an oscillating background that violates parity and time-reversal symmtries. Inside piezoelectric crystals, where parity is broken spontaneously, this axion background can result in a stress. We call this new phenomenon “the piezoaxionic effect.” When the frequency of axion DM matches the natural frequency of a bulk acoustic normal mode of the piezoelectric crystal, the piezoaxionic effect is resonantly enhanced and can be read out electrically via the piezoelectric effect. We explore all axion couplings that can give rise to the piezoaxionic effect—the most promising one is the defining coupling of the QCD axion, through the anomaly of the strong sector. We also point our another, subdominant phenomenon present in all dielectrics, namely the “electroaxionic effect.” An axion background can produce an electric displacement field in a crystal which in turn will give rise to a voltage across the crystal. The electroaxionic effect is again largest for the axion coupling to gluons. We find that this model-independent coupling of the QCD axion may be probed through the combination of the piezoaxionic and electroaxionic effects in piezoelectric crystals with aligned nuclear spins, with near-future experimental setups applicable for axion masses between 10^−11  eV and 10^−7  eV, a challenging range for most other detection concepts. 

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2. Auger effect limited performance in tunnel field effect transistors

   https://doi.org/10.1109/E3S.2017.8246156  

   Ahmed, Sheikh; Tan, Yaohua; Truesdell, Daniel; Ghosh, Avik (October 2017, 2017 Fifth Berkeley Symposium on Energy Efficient Electronic Systems & Steep Transistors Workshop (E3S))

   null (Ed.)

   Tunnel field-effect-transistors (TFETs) are promising candidates for next generation transistors for low power applications, as the TFETs promise low subthreshold swing (SS). Different from traditional MOSFET, the TFETs rely on energy-efficient switching of band-to-band tunneling (BTBT), therefore the SS in TFETs is not limited by the 60 mV/decade Boltzmann limit. This reduction in energy consumption makes TFETs suitable candidates to replace standard MOSFETs in low power applications. However, most experimentally demonstrated TFETs suffer from low on current[1], and the theoretical low SS is compromised by impurities and Auger generation. To understand the underlying physics and predict the device characteristics of TFETs, sophisticated numerical simulations can be used. On the other hand, physics based compact models are also required to provide fast predictions for existing and new device concepts. Furthermore, a physics based compact model is more efficient to model the effects like Auger generation which could be time-consuming for numerical calculations. In this work, we introduce a physics based compact model for homojunction TFETs with Auger generation effect considered. This compact model is based on the modified Simmons' equation at finite temperature[2]. With our compact model, the possible impact of Auger generation effect to off-current and SS is explored. 

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3. The Effect of Directed Movement on the Strong Allee Effect

   https://doi.org/10.1137/20M1330178  

   Cosner, Chris; Rodriguez, Nancy (January 2021, SIAM Journal on Applied Mathematics)

   null (Ed.)
4. Effect-Centric Networking

   https://doi.org/10.1109/ICDCSW53096.2021.00017  

   Liu, H.; Chen, X. (July 2021, 2021 IEEE 41st International Conference on Distributed Computing Systems)
5. Hall Effect in Polycrystalline Organic Semiconductors: The Effect of Grain Boundaries

   https://doi.org/10.1002/adfm.201903617  

   Choi, Hyun Ho; Paterson, Alexandra F.; Fusella, Michael A.; Panidi, Julianna; Solomeshch, Olga; Tessler, Nir; Heeney, Martin; Cho, Kilwon; Anthopoulos, Thomas D.; Rand, Barry P.; et al (July 2019, Advanced Functional Materials)

   Abstract Highly crystalline thin films in organic semiconductors are important for applications in high‐performance organic optoelectronics. Here, the effect of grain boundaries on the Hall effect and charge transport properties of organic transistors based on two exemplary benchmark systems is elucidated: (1) solution‐processed blends of 2,7‐dioctyl[1]benzothieno[3,2‐b][1]benzothiophene (C₈‐BTBT) small molecule and indacenodithiophene‐benzothiadiazole (C₁₆IDT‐BT) conjugated polymer, and (2) large‐area vacuum evaporated polycrystalline thin films of rubrene (C₄₂H₂₈). It is discovered that, despite the high field‐effect mobilities of up to 6 cm²V⁻¹s⁻¹and the evidence of a delocalized band‐like charge transport, the Hall effect in polycrystalline organic transistors is systematically and significantly underdeveloped, with the carrier coherence factor α < 1 (i.e., yields an underestimated Hall mobility and an overestimated carrier density). A model based on capacitively charged grain boundaries explaining this unusual behavior is described. This work significantly advances the understanding of magneto‐transport properties of organic semiconductor thin films. 

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