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1. Room temperature terahertz quantum cascade laser sources with 215  μ W output power through epilayer-down mounting

   https://doi.org/10.1063/1.4812814  

   Lu, Q Y; Bandyopadhyay, N; Slivken, S; Bai, Y; Razeghi, M (July 2013, Applied Physics Letters)

   We report room temperature terahertz (THz) quantum cascade laser sources with high power based on difference frequency generation. The device is Čerenkov phase matched and spectrally purified with an integrated dual-period distributed-feedback grating. Symmetric current injection and epilayer-down mounting of the device onto a patterned submount are used to improve the electrical uniformity and heat removal, respectively. The epilayer-down mounting also allows for THz anti-reflective coating to enhance the THz outcoupling efficiency. Single mode emission at 3.5 THz with a side-mode suppression ratio and output power up to 30 dB and 215 μW are obtained, respectively. 

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2. A 99.9% Efficient, Ultra-Low Power Automated On/Off Adaptive MPPT Circuit for RF, PV, and TEG Sources From 1 μ W to 4 mW

   https://doi.org/10.1109/TCSI.2025.3603951  

   Abedi, Mostafa; Shrivastava, Aatmesh (September 2025, IEEE Transactions on Circuits and Systems I: Regular Papers)
3. Redetermination of poly[di-μ ₃ -iodido-[μ-1,2- trans -(pyridin-4-yl)ethene-κ ² N : N ′]dicopper(I)]

   https://doi.org/10.1107/S2414314619001226  

   Neal, Henry C.; Tamtam, Harsha; Smucker, Bradley W.; Nesterov, Volodymyr V. (January 2019, IUCrData)

   The re-investigated structure of the title compound, [Cu 2 I 2 (C 12 H 10 N 2 )] n , a two-dimensional coordination polymer crystallizing with monoclinic ( P 2 1 / n ) symmetry, is based on data collected at 100 K, while the previously reported structure was obtained with data collected at 203 K [Blake et al. (1999). Cryst. Eng. 2 , 181–195]. The refinement of the crystal structure is greatly improved; for example, the wR 2 residual converges to 0.047 for 1532 independent data, versus wR 2 = 0.179 for 992 independent data in the 1999 study. 

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4. Continuous wave interband cascade lasers near 13  μ m

   https://doi.org/10.1116/6.0003365  

   Shen, Yixuan; Yang, Rui Q; Hawkins, S D; Muhowski, A J (March 2024, Journal of Vacuum Science & Technology B)

   We report the demonstration of continuous-wave interband cascade lasers (ICLs) near 13 μm. The attained lasing wavelength of 13.2 μm at 92 K stands as the longest cw emission wavelength ever reported for III-V interband lasers. This achievement is attributed to the adoption of an innovative quantum well (QW) active region comprising strained InAs0.5P0.5 layers in contrast to the commonly used “W” QW active region, showing the potential of the modified QW active region with InAsP layers in improving device performance and extending wavelength coverage of ICLs. 

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5. The 2022 M _W 7.3 Southern Sumatra Tsunami Earthquake: Rupture Up‐Dip of the 2007 M _W 8.4 Bengkulu Event

   https://doi.org/10.1029/2024JB030284  

   Xia, Tao; Ye, Lingling; Bai, Yefei; Lay, Thorne; Xu, Shiqing; Kanamori, Hiroo; Rivera, Luis; Dwi_Sriyanto, Sesar_Prabu (December 2024, Journal of Geophysical Research: Solid Earth)

   Abstract On 18 November 2022, a large earthquake struck offshore southern Sumatra, generating a tsunami with 25 cm peak amplitude recorded at tide gauge station SBLT. OurW‐phase solution indicates a shallow dip of 6.2°, compatible with long‐period surface wave radiation patterns. Inversion of teleseismic body waves indicates a shallow slip distribution extending from about 10 km deep to near the trench with maximum slip of ∼4.1 m and seismic moment of  Nm (M_W7.3). Joint modeling of seismic and tsunami data indicates a shallow rigidity of ∼23 GPa. We find a low moment‐scaled radiated energy of , similar to that of the 2010M_W7.8 Mentawai event () and other tsunami earthquakes. These characteristics indicate that the 2022 event should be designated as a smaller moment magnitude tsunami earthquake compared to the other 12 well‐documented global occurrences since 1896. The 2022 event ruptured up‐dip of the 2007M_W8.4 Bengkulu earthquake, demonstrating shallow seismogenic capability of a megathrust that had experienced both a deeper seismic event and adjacent shallow aseismic afterslip. We consider seismogenic behavior of shallow megathrusts and concern for future tsunami earthquakes in subduction zones globally, noting a correlation between tsunami earthquake occurrence and subducting seafloor covered with siliceous pelagic sediments. We suggest that the combination of pelagic clay and siliceous sediments and rough seafloor topography near the trench play important roles in controlling the genesis of tsunami earthquakes along Sumatra and other regions, rather than the subduction tectonic framework of accretionary or erosive margin. 

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