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1. Tripling of the superconducting critical current density in BaFe ${}_2$ (As ${}_{1-x}$ P ${}_x$ ) ${}_2$ retained after pressure release

   https://doi.org/10.1088/1361-6668/ae702f  

   Liu, Jiangteng; Lopez, Alex; Slone, Daniel; Ren, Guodong; Liu, Zhaoyu; Idrobo, Juan-Carlos; Chu, Jiun-Haw; Eley, Serena (June 2026, Superconductor Science and Technology)

   Abstract Superconducting performance is tunable not only via chemical modification or defect engineering, but also through external parameters such as pressure, though this method remains less readily accessible. In this work, we study how compression influences vortex dynamics and critical currents in an iron-based superconductor. Specifically, we perform magnetization measurements using an off-the-shelf pressure cell to investigate the effects of hydrostatic pressures up to 1.08 GPa on the magnetic properties of BaFe ${}_2$ (As ${}_{0.62}$ P ${}_{0.38}$ ) ${}_2$ crystals across a range of temperatures $T$ and magnetic fields $H$ . Although these pressures minimally affect the superconducting critical temperature, they produce a clear increase in the critical current density $J_{\mathrm{c}}(T,H)$ , a pronounced reduction in the rate of thermally activated vortex motion $S(T,H)$ , and can change the dominant vortex pinning mechanism. Furthermore, the effects of pressure are irreversible: after pressurization and subsequent release at room temperature, high-density microcracks are observed and the crystals retain their enhanced critical current densities. The second magnetization peak vanishes above 18 K after the pressure cycle, which we attribute to a transition from predominantly $\delta \kappa$ pinning to a mixed mechanism of $\delta T_{\mathrm{c}}$ and surface pinning. Lastly, a threefold increase in $J_{\mathrm{c}}$ , a more than 40% reduction in $S$ at 8 K and 0.5 T, and an expanded elastic-creep region were achieved after $1-2$ pressure cycles. These findings demonstrate the potential utility of pressure cycling for improving $J_{\mathrm{c}}$ , which may offer a simpler alternative compared to approaches such as chemical doping or the introduction of artificial pinning centers. 

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2. Fermi-level Dirac crossings in $4d$ and $5d$ cubic metal oxides: ${\mathrm{NaPd}}_3{\mathrm{O}}_4$ and ${\mathrm{NaPt}}_3{\mathrm{O}}_4$

   https://doi.org/10.1103/PhysRevB.99.195148  

   Teicher, Samuel M.; Lamontagne, Leo K.; Schoop, Leslie M.; Seshadri, Ram (May 2019, Physical Review B)
3. Origin of the orbital polarization of ${\mathrm{Co}}^{2+}$ in ${\mathrm{La}}_2{\mathrm{CoTiO}}_6$ and ( ${\mathrm{LaCoO}}_3{)}_1+{\left({\mathrm{LaTiO}}_3\right)}_1$ : A $\mathrm{DFT}+U$ and DFMT study

   https://doi.org/10.1103/PhysRevB.103.125105  

   Lee, Alex Taekyung; Park, Hyowon; Ismail-Beigi, Sohrab (March 2021, Physical Review B)

   null (Ed.)
4. Spreading resistance effects in tunneling spectroscopy of $\alpha \text{−}{\mathrm{RuCl}}_3$ and ${\mathrm{Ir}}_{0.5}{\mathrm{Ru}}_{0.5}{\mathrm{Cl}}_3$

   https://doi.org/10.1103/PhysRevB.108.245410  

   Frick, Jordan R; Sridhar, Samanvitha; Khansari, Ario; Comstock, Andrew H; Norman, Elizabeth; O’Donnell, Shaun; Maggard, Paul A; Sun, Dali; Dougherty, Daniel B (December 2023, Physical Review B)
5. Uniaxial $c$ -axis pressure effects on the underdoped superconductor ${\mathrm{BaFe}}_2({\mathrm{As}}_{0.72}{\mathrm{P}}_{0.28}{)}_2$

   https://doi.org/10.1103/PhysRevB.101.020507  

   Hu, Ding; Tam, David W.; Zhang, Wenliang; Wei, Yuan; Georgii, Robert; Pedersen, Björn; Roldan, Alfonso Chacon; Dai, Pengcheng (January 2020, Physical Review B)