TY - RPRT TI - Efficient ptychographic phase retrieval via a matrix-free Levenberg-Marquardt algorithm AU - Kandel, Saugat (ORCID:0000000273242559) AU - Maddali, S. (ORCID:0000000345166250) AU - Nashed, Youssef S. G. (ORCID:0000000161463939) AU - Hruszkewycz, Stephan O. (ORCID:0000000293949252) AU - Jacobsen, Chris (ORCID:0000000185620353) AU - Allain, Marc PY - 2021 DO - 10.1364/oe.422768 UR - https://www.osti.gov/biblio/1806256 ID - 1806256 ER -