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Kristine Lang, Dustin Hite, Raymond Simmonds, Robert McDermott, David P. Pappas, John M. Martinis
Increasing demands on nanometer scale properties of oxide tunnel barriers necessitate a consistent means to assess them at these lengths. Here we use conducting atomic force microscopy (CAFM) to characterize aluminum oxide (AlOx)barriers to be used in
Raymond Simmonds, Kristine Lang, Dustin Hite, David P. Pappas, John M. Martinis
We present experimental data that demonstrates a large reduction in the coherence of a Josephson phase qubit from spurious microwave resonances. These resonances are believed to arise from resonant fluctuators in the tunnel junction that couple to the
Murray D. Barrett, Tobias Schaetz, J Chiaverini, Dietrich Leibfried, Joseph W. Britton, Wayne M. Itano, John D. Jost, Emanuel Knill, C. Langer, R Ozeri, David J. Wineland
We report experiments on the creation and manipulation ofmulti-particle entangled states of trapped atomic ions. The experiments reported here, quantum dense coding and quantum teleportation, constitute a significant step toward performing large-scale
Steven Deiker, William B. Doriese, Gene C. Hilton, Kent D. Irwin, William H. Rippard, Joel N. Ullom, Leila R. Vale, Steve T. Ruggiero, Anthony Williams, B. Young
We have fabricated a bolometer using a transition-edge sensor (TES) made of Al doped with Mn to suppress the superconducting critical temperature !Tc" of Al from #1 K to #100 mK. The resulting detector exhibits low-frequency noise consistent with theory
A Bartels, Scott A. Diddams, Christopher W. Oates, G Wilpers, Windell Oskay, James C. Bergquist, Leo W. Hollberg
A femtosecond laser frequency comb transfers the low phase and frequency noise of a cavity-stabilized CW laser to the microwave domain. Phase noise of -115 dBc/Hz at 1 Hz offset from the 1 GHz carrier is achieved.
Long-Sheng Ma, Lennart Robertsson, Massimo Zucco, Zhiyi Bi, Robert Windeler, A Bartels, G Wilpers, Christopher W. Oates, Leo W. Hollberg, Scott Diddams
We compare the accuracy of femtosecond laser optical frequency synthesizers that employ microstructured fibers with those that directly generate a broadband output. No limitation of either system is found at fractional frequency levels of 1x10 -18.
Joel N. Ullom, William B. Doriese, Gene C. Hilton, James A. Beall, Steven Deiker, William Duncan, S. L. Ferreira, Kent D. Irwin, Carl D. Reintsema, Leila R. Vale
The noise in superconducting Transition-Edge Sensors (TESs) commonly exceeds simple theoretical predictions. The reason for this discrepancy is presently unexplained. We have measured the amplitude and frequency dependence of the noise in TES sensors with
The polarization of a nearest-neighbor (nn) Pb-O vacancy pair in PbTiO3 is calculated, using the modern theory of polarization, implemented in the density functional theory ultrasoft pseudopotential formalism. The dipole moment per divacancy is about 2.228
Here we describe in a historical manner the first optical frequency measurement measurements with octave-spanning frequency combs and the first measurement and stabilization of the carrier-envelope offset frequency for a train of femtosecond laser pulses.
We have measured the maximum field for which vortices are completely expelled from a thin-film superconducting strip. Niobium strips of width W were field cooled and imaged with a scanning Hallprobe microscope. Below a critical field Bm 0=W2 all flux
Akira Fujiwara, Neil M. Zimmerman, Yukinori Ono, Yasuo Takahashi
We observe a quantized current due to single-electron transfer in a small charge-coupled device, which consists of a narrow Si-wire channel with fine gates; the gate is used to form a tunable barrier potential. By modulating two barrier potentials under
We demonstrate the degrading effect of noise from amplified spontaneous emission on measurements of chromatic dispersion using the modulation phase-shift method. Dramatic performance improvement is achieved with a narrow-band tracking filter.
Kristan L. Corwin, I Thomann, A Bartels, Tasshi Dennis, W. Fox, William C. Swann, E. A. Curtis, C. W. Oates, G Wilpers, Sarah L. Gilbert, Leo W. Hollberg, Nathan R. Newbury, Scott A. Diddams, Jeffrey W. Nicholson, M. Yan
A frequency comb is generated with a chromium-doped forsterite femtosecond laser, spectrally broadened in dispersion-shifted highly nonlinear fiber, and stabilized. The resultant evenly spaced comb of frequencies ranges from 1.1 to beyond 1.8 υm. The
K L. Corwin, I Thomann, A Bartels, T Dennis, Richard W. Fox, W C. Swann, E A. Curtis, Christopher W. Oates, G Wilpers, S L. Gilbert, Leo W. Hollberg, Nathan R. Newbury, Scott Diddams, J Nicholson, M. F. Yan
We consider the radiation force on highly dispersive media. In doing so we reconsider an experiment proposed to measure the Abraham force term in the stress-energy tensor at optical frequencies by measuring the displacement of a transparent dielectric
Terrence J. Jach, S. Kim, J. A. Aust, S M. Durbin, David S. Bright
rroelectric domains with antiparallel polarization are readily induced in congruent LiNbO3 with electric fields above 240 kV/cm at room temperature. Even in the absence of external fields, these 180 walls exhibit wide regions of shear strain, of the order
We describe in detail our implementation of a modulation phase shift (MPS) technique for narrow-bandwidth measurement of differential group delay (DGD) and the principal states of polarization (PSP) in optical fibers and components. Out MPS technique
Susan Y. Lehman, Kristine A. Bertness, Joseph T. Hodges
We have utilized cavity ring-down spectroscopy (CRDS) to characterize the pressure and carrier gas effects on the shape of a water absorption line. The half-width at half-maximum (HWHM) pressure-broadening coefficient for the water line at 10687.36 cm -1