25,587 research outputs found
The Accessible Toilet Resource
Extract: This Accessible Toilet Design Resource has been produced from new primary research carried out within VivaCity 2020, a large university-based research consortium that is developing tools and resources to support the design of socially inclusive cities. The consortium is funded by the Engineering and Physical Sciences Research Council (EPSRC). It was set up in 2003 and will complete its work in 2008. The Resource is concerned primarily with the design of the accessible toilet cubicle that should be provided for customer or public use wherever there is standard toilet provision. Though it may make reference to other types of toilet cubicles, urinals, automatic public conveniences (APCs) or grouped toilet provision, the location and design of these facilities are not addressed in great detail here. The location and design of accessible toilet facilities merits this independent, detailed scrutiny because it is essential to provide these facilities and to design them correctly, so that disabled people can participate on equal terms to able-bodied people in every aspect of city life
Fast Single-Charge Sensing with an rf Quantum Point Contact
We report high-bandwidth charge sensing measurements using a GaAs quantum
point contact embedded in a radio frequency impedance matching circuit
(rf-QPC). With the rf-QPC biased near pinch-off where it is most sensitive to
charge, we demonstrate a conductance sensitivity of 5x10^(-6) e^(2)/h Hz^(-1/2)
with a bandwidth of 8 MHz. Single-shot readout of a proximal few-electron
double quantum dot is investigated in a mode where the rf-QPC back-action is
rapidly switched.Comment: related papers available at http://marcuslab.harvard.ed
Two-way time transfers between NRC/NBS and NRC/USNO via the Hermes (CTS) satellite
At each station the differences were measured between the local UTC seconds pulse and the remote UTC pulse received by satellite. The difference between the readings, if station delays are assumed to be symmetrical, is two times the difference between the clocks at the two ground station sites. Over a 20-minute period, the precision over the satellite is better than 1 ns. The time transfer from NRC to the CRC satellite terminal near Ottawa and from NBS to the Denver HEW terminal was examined
Interlaced Dynamical Decoupling and Coherent Operation of a Singlet-Triplet Qubit
We experimentally demonstrate coherence recovery of singlet-triplet
superpositions by interlacing qubit rotations between Carr-Purcell (CP) echo
sequences. We then compare performance of Hahn, CP, concatenated dynamical
decoupling (CDD) and Uhrig dynamical decoupling (UDD) for singlet recovery. In
the present case, where gate noise and drift combined with spatially varying
hyperfine coupling contribute significantly to dephasing, and pulses have
limited bandwidth, CP and CDD yield comparable results, with T2 ~ 80
microseconds.Comment: related papers at http://marcuslab.harvard.ed
Rapid Single-Shot Measurement of a Singlet-Triplet Qubit
We report repeated single-shot measurements of the two-electron spin state in
a GaAs double quantum dot. The readout scheme allows measurement with fidelity
above 90% with a 7 microsecond cycle time. Hyperfine-induced precession between
singlet and triplet states of the two-electron system are directly observed, as
nuclear Overhauser fields are quasi-static on the time scale of the measurement
cycle. Repeated measurements on millisecond to second time scales reveal
evolution of the nuclear environment.Comment: supplemental material at
http://marcuslab.harvard.edu/papers/single_shot_sup.pd
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