title: Atomic vapor cells for chip-scale atomic clocks with improved long-term frequency stability.
abstract: A novel technique for microfabricating alkali atom vapor cells is described in which alkali atoms are evaporated into a micromachined cell cavity through a glass nozzle. A cell of interior volume 1 mm3, containing 87Rb and a buffer gas, was made in this way and integrated into an atomic clock based on coherent population trapping. A fractional frequency instability of 6 x 10(-12) at 1000 s of integration was measured. The long-term drift of the F=1, mF=0-->F=2, mF=0 hyperfine frequency of atoms in these cells is below 5 x 10(-11)/day.
authors.affiliation: Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 8030, USA. knappe@boulder.nist.gov
authors.forename: S
authors.initials: S
authors.lastname: Knappe
authors.forename: V
authors.initials: V
authors.lastname: Gerginov
authors.forename: P D D
authors.initials: PD
authors.lastname: Schwindt
authors.forename: V
authors.initials: V
authors.lastname: Shah
authors.forename: H G
authors.initials: HG
authors.lastname: Robinson
authors.forename: L
authors.initials: L
authors.lastname: Hollberg
authors.forename: J
authors.initials: J
authors.lastname: Kitching