Libration of strongly oriented polar molecules inside a superfluid Redchenko, Elena Lemeshko, Mikhail ; https://orcid.org/0000-0002-6990-7802 We study a polar molecule immersed in a superfluid environment, such as a helium nanodroplet or a Bose–Einstein condensate, in the presence of a strong electrostatic field. We show that coupling of the molecular pendular motion, induced by the field, to the fluctuating bath leads to formation of pendulons—spherical harmonic librators dressed by a field of many-particle excitations. We study the behavior of the pendulon in a broad range of molecule–bath and molecule–field interaction strengths, and reveal that its spectrum features a series of instabilities which are absent in the field-free case of the angulon quasiparticle. Furthermore, we show that an external field allows to fine-tune the positions of these instabilities in the molecular rotational spectrum. This opens the door to detailed experimental studies of redistribution of orbital angular momentum in many-particle systems. © 2016 Wiley-VCH Verlag GmbH &amp; Co. KGaA, Weinheim Wiley-Blackwell 2016 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/1206 Redchenko E, Lemeshko M. Libration of strongly oriented polar molecules inside a superfluid. <i>ChemPhysChem</i>. 2016;17(22):3649-3654. doi:<a href="https://doi.org/10.1002/cphc.201601042">10.1002/cphc.201601042</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1002/cphc.201601042 info:eu-repo/semantics/altIdentifier/wos/000388625000008 info:eu-repo/semantics/altIdentifier/arxiv/1609.08161 info:eu-repo/semantics/openAccess