@article{21382,
  abstract     = {The exceptional energy-harvesting efficiency of lead-halide perovskites arises from unusually long photocarrier diffusion lengths and recombination lifetimes that persist even in defect-rich, solution-grown samples. Paradoxically, perovskites are also known for having very short exciton decay times. Here, we resolve this apparent contradiction by showing that key optoelectronic properties of perovskites can be explained by localized flexoelectric polarization confined to interfaces between domains of spontaneous strain. Using birefringence imaging, electrochemical staining, and zero-bias photocurrent measurements, we visualize the domain structure and directly probe the associated internal fields in nominally cubic single crystals of methylammonium lead bromide. We demonstrate that localized flexoelectric fields spatially separate electrons and holes to opposite sides of domain walls, exponentially suppressing recombination. Domain walls thus act as efficient mesoscopic transport channels for long-lived photocarriers, microscopically linking structural heterogeneity to charge transport and offering mechanistically informed design principles for perovskite solar-energy technologies.},
  author       = {Rak, Dmytro and Lorenc, Dusan and Balazs, Daniel and Zhumekenov, Ayan A. and Bakr, Osman M. and Alpichshev, Zhanybek},
  issn         = {2041-1723},
  journal      = {Nature Communications},
  publisher    = {Springer Nature},
  title        = {{Flexoelectric domain walls enable charge separation and transport in cubic perovskites}},
  doi          = {10.1038/s41467-026-68660-5},
  volume       = {17},
  year         = {2026},
}

@article{20705,
  abstract     = {Optical tweezers are widely used as a highly sensitive tool to measure forces on micron-scale particles. One such application is the measurement of the electric charge of a particle, which can be done with high precision in liquids, air, or vacuum. We experimentally investigate how the trapping laser itself can electrically charge such a particle, in our case a ∼1  μ⁢m SiO2 sphere in air. We model the charging mechanism as a two-photon process which reproduces the experimental data with high fidelity.},
  author       = {Stöllner, Andrea and Lenton, Isaac C and Volosniev, Artem and Millen, James and Shibuya, Renjiro and Ishii, Hisao and Rak, Dmytro and Alpichshev, Zhanybek and David, Grégory and Signorell, Ruth and Muller, Caroline J and Waitukaitis, Scott R},
  issn         = {1079-7114},
  journal      = {Physical Review Letters},
  number       = {21},
  publisher    = {American Physical Society},
  title        = {{Using optical tweezers to simultaneously trap, charge, and measure the charge of a microparticle in air}},
  doi          = {10.1103/5xd9-4tjj},
  volume       = {135},
  year         = {2025},
}