title: Spectroscopy and thermometry of drumhead modes in a mesoscopic trapped-ion crystal using entanglement.
abstract: We demonstrate spectroscopy and thermometry of individual motional modes in a mesoscopic 2D ion array using entanglement-induced decoherence as a method of transduction. Our system is a ~400 μm-diameter planar crystal of several hundred 9Be(+) ions exhibiting complex drumhead modes in the confining potential of a Penning trap. Exploiting precise control over the 9Be(+) valence electron spins, we apply a homogeneous spin-dependent optical dipole force to excite arbitrary transverse modes with an effective wavelength approaching the interparticle spacing (~20 μm). Center-of-mass displacements below 1 nm are detected via the entanglement of spin and motional degrees of freedom.
authors.affiliation: Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305, USA. brian.sawyer@boulder.nist.gov
authors.forename: Brian C
authors.initials: BC
authors.lastname: Sawyer
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Britton
authors.forename: Adam C
authors.initials: AC
authors.lastname: Keith
authors.forename: C-C Joseph
authors.initials: CC
authors.lastname: Wang
authors.forename: James K
authors.initials: JK
authors.lastname: Freericks
authors.forename: Hermann
authors.initials: H
authors.lastname: Uys
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Biercuk
authors.forename: John J
authors.initials: JJ
authors.lastname: Bollinger