224 research outputs found
Robust design under uncertainty in quantum error mitigation
Error mitigation techniques are crucial to achieving near-term quantum
advantage. Classical post-processing of quantum computation outcomes is a
popular approach for error mitigation, which includes methods such as Zero
Noise Extrapolation, Virtual Distillation, and learning-based error mitigation.
However, these techniques have limitations due to the propagation of
uncertainty resulting from a finite shot number of the quantum measurement. To
overcome this limitation, we propose general and unbiased methods for
quantifying the uncertainty and error of error-mitigated observables by
sampling error mitigation outcomes. These methods are applicable to any
post-processing-based error mitigation approach. In addition, we present a
systematic approach for optimizing the performance and robustness of these
error mitigation methods under uncertainty, building on our proposed
uncertainty quantification methods. To illustrate the effectiveness of our
methods, we apply them to Clifford Data Regression in the ground state of the
XY model simulated using IBM's Toronto noise model.Comment: 9 pages, 5 figure
2-(4-MethylÂphenÂyl)-1H-anthraceno[1,2-d]imidazole-6,11-dione: a fluorescent chemosensor
In the title compound, C22H14N2O2, the five rings of the molÂecule are not coplanar. There is a significant twist between the four fused rings, which have a slightly arched conformation, and the pendant aromatic ring, as seen in the dihedral angle of 13.16 (8)° between the anthraquinonic ring system and the pendant aromatic ring plane
Mitiq : a software package for error mitigation on noisy quantum computers
We introduce Mitiq, a Python package for error mitigation on noisy quantum computers. Error mitigation techniques can reduce the impact of noise on near-term quantum computers with minimal overhead in quantum resources by relying on a mixture of quantum sampling and classical post-processing techniques. Mitiq is an extensible toolkit of different error mitigation methods, including zero-noise extrapolation, probabilistic error cancellation, and Clifford data regression. The library is designed to be compatible with generic backends and interfaces with different quantum software frameworks. We describe Mitiq using code snippets to demonstrate usage and discuss features and contribution guidelines. We present several examples demonstrating error mitigation on IBM and Rigetti superconducting quantum processors as well as on noisy simulators
Unambiguous detection of nitrated explosive vapours by fluorescence quenching of dendrimer films
Unambiguous and selective standoff (non-contact) infield detection of nitro-containingexplosives and taggants is an important goal but difficult to achieve with standard analyticaltechniques. Oxidative fluorescence quenching is emerging as a high sensitivity method fordetecting such materials but is prone to false positives—everyday items such as perfumeselicit similar responses. Here we report thin films of light-emitting dendrimers that detectvapours of explosives and taggants selectively—fluorescence quenching is not observed for arange of common interferents. Using a combination of neutron reflectometry, quartz crystalmicrobalance and photophysical measurements we show that the origin of the selectivity isprimarily electronic and not the diffusion kinetics of the analyte or its distribution in the film.The results are a major advance in the development of sensing materials for the standoffdetection of nitro-based explosive vapours, and deliver significant insights into the physicalprocesses that govern the sensing efficacy
Degualinium v lechenii belejj na fone nespecificheskogo vospalenija vlagalishha
Beneficial results of Degualinium therapy obtained in the inflammatory conditions of vaginal mucous membranes, particularly in vaginal trichomonadosis, are reported
Degualinium v lechenii belejj na fone nespecificheskogo vospalenija vlagalishha
Beneficial results of Degualinium therapy obtained in the inflammatory conditions of vaginal mucous membranes, particularly in vaginal trichomonadosis, are reported
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