title: Spin waves and dielectric softening of polar molecule condensates.
abstract: We consider an oblate Bose-Einstein condensate of heteronuclear polar molecules in a weak applied electric field. This system supports a rich quasiparticle spectrum that plays a critical role in determining its bulk dielectric properties. In particular, in sufficiently weak fields the system undergoes a polarization wave rotonization, leading to the development of textured electronic structure and a dielectric instability that is characteristic of the onset of a negative static dielectric function.
authors.affiliation: Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, Gaithersburg, Maryland 20899, USA.
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Wilson
authors.affiliation: Department of Physics and Astronomy, Western Washington University, Bellingham, Washington 98225, USA.
authors.forename: Brandon M
authors.initials: BM
authors.lastname: Peden
authors.affiliation: Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, Gaithersburg, Maryland 20899, USA.
authors.forename: Charles W
authors.initials: CW
authors.lastname: Clark
authors.affiliation: Department of Physics and Astronomy, Western Washington University, Bellingham, Washington 98225, USA and ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA.
authors.forename: Seth T
authors.initials: ST
authors.lastname: Rittenhouse