1,716 research outputs found
Qubit Reset with a Shortcut-to-Isothermal Scheme
Landauer's principle shows that the minimum energy cost to reset a classical
bit in a bath with temperature is in the infinite time.
However, the task to reset the bit in finite time has posted a new challenge,
especially for quantum bit (qubit) where both the operation time and
controllability are limited. We design a shortcut-to-isothermal scheme to reset
a qubit in finite time with limited controllability. The energy cost is
minimized with the optimal control scheme with and without nonholonomic
constraint. This optimal control scheme can provide a reference to realize
qubit reset with minimum energy cost for the limited time.Comment: 8 pages, 7 figure
Speed limitation of a mobile robot and methodology of tracing odor plume in airflow environments
AbstractThe methodology of tracing odor plume via a mobile robot is considered. In this research, two typical plume-tracing methods, i.e., a zigzagging method and an upwind method, are tested in four airflow fields with different long-time average wind speeds when the robot is set to possessing four different maximum speeds. According to the simulation results, it can be deduced that the zigzagging algorithms would be efficient when the robot moves faster than the odor plume or airflow, and the upwind algorithms are preferred especially when the robot is slow
Spurious Shell Closures in the Relativistic Mean Field Model
Following a systematic theoretical study of the ground-state properties of
over 7000 nuclei from the proton drip line to the neutron drip line in the
relativistic mean field model [Prog. Theor. Phys. 113 (2005) 785], which is in
fair agreement with existing experimental data, we observe a few spurious shell
closures, i.e. proton shell closures at Z=58 and Z=92. These spurious shell
closures are found to persist in all the effective forces of the relativistic
mean field model, e.g. TMA, NL3, PKDD and DD-ME2.Comment: 3 pages, to appear in Chinese Physics Letter
The Effect of GABAA Receptor on Information Capacity of Cultured Hippocampal Neurons
Neural information is encoded by action potentials delivered by neurons. Which component of neural activity constitutes the basic unit carrying information is still a controversial issue. In this paper, stimulation experiments using a network of hippocampal neurons cultured on a multi-electrode array are used to investigate this issue. The results show that for a set of pulse stimuli with varying voltage amplitude, the neuronal response to the fronto-potential sequence encodes more information through the moment of fronto-potential delivery than the number of fronto-potential deliveries, and that neurons at each locus are encoded independently of each other. After the addition of bicuculline inhibited the GABAA receptors, the information capacity decreased and the temporal resolution decreased, but the neurons at each site were still encoded independently. The results suggest that the encoding of stimulus amplitude in the cultured hippocampal neuronal network is better with spike timing than with count, and the effect of timing encoding is dependent on GABAA receptors
Characterizing Kirkwood-Dirac nonclassicality and uncertainty diagram based on discrete Fourier transform
In this paper, we investigate the Kirkwood-Dirac nonclassicality and
uncertainty diagram based on discrete Fourier transform (DFT) in a
dimensional system. The uncertainty diagram of complete incompatibility bases
are characterized by De Bi\`{e}vre [arXiv:
2207.07451]. We show that for the uncertainty diagram of the DFT matrix which
is a transition matrix from basis to basis , there
is no ``hole" in the region of the -plane
above and on the line , whether the
bases are not complete incompatible bases or not.
Then we present that the KD nonclassicality of a state based on the DFT matrix
can be completely characterized by using the support uncertainty relation
, where and count the number of nonvanishing
coefficients in the basis and representations,
respectively. That is, a state is KD nonclassical if and only if
, whenever is prime or
not. That gives a positive answer to the conjecture in [Phys. Rev. Lett.
\textbf{127}, 190404 (2021)]
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