1,052 research outputs found
IDF-Autoware: Integrated Development Framework for ROS-Based Self-Driving Systems Using MATLAB/Simulink
This paper proposes an integrated development framework that enables co-simulation and operation of a Robot Operating System (ROS)-based self-driving system using MATLAB/Simulink (IDF-Autoware). The management of self-driving systems is becoming more complex as the development of self-driving technology progresses. One approach to the development of self-driving systems is the use of ROS; however, the system used in the automotive industry is typically designed using MATLAB/Simulink, which can simulate and evaluate the models used for self-driving. These models are incompatible with ROS-based systems. To allow the two to be used in tandem, it is necessary to rewrite the C++ code and incorporate them into the ROS-based system, which makes development inefficient. Therefore, the proposed framework allows models created using MATLAB/Simulink to be used in a ROS-based self-driving system, thereby improving development efficiency. Furthermore, our evaluations of the proposed framework demonstrated its practical potential
Classically Simulating Quantum Circuits with Local Depolarizing Noise
We study the effect of noise on the classical simulatability of quantum circuits defined by computationally tractable (CT) states and efficiently computable sparse (ECS) operations. Examples of such circuits, which we call CT-ECS circuits, are IQP, Clifford Magic, and conjugated Clifford circuits. This means that there exist various CT-ECS circuits such that their output probability distributions are anti-concentrated and not classically simulatable in the noise-free setting (under plausible assumptions). First, we consider a noise model where a depolarizing channel with an arbitrarily small constant rate is applied to each qubit at the end of computation. We show that, under this noise model, if an approximate value of the noise rate is known, any CT-ECS circuit with an anti-concentrated output probability distribution is classically simulatable. This indicates that the presence of small noise drastically affects the classical simulatability of CT-ECS circuits. Then, we consider an extension of the noise model where the noise rate can vary with each qubit, and provide a similar sufficient condition for classically simulating CT-ECS circuits with anti-concentrated output probability distributions
Phase and amplitude of Aharonov-Bohm oscillations in nonlinear three-terminal transport through a double quantum dot
We study three-terminal linear and nonlinear transport through an
Aharonov-Bohm interferometer containing a double quantum dot using the
nonequilibrium Green's function method. Under the condition that one of the
three terminals is a voltage probe, we show that the linear conductance is
symmetric with respect to the magnetic field (phase symmetry). However, in the
nonlinear transport regime, the phase symmetry is broken. Unlike two-terminal
transport, the phase symmetry is broken even in noninteracting electron
systems. Based on the lowest-order nonlinear conductance coefficient with
respect to the source-drain bias voltage, we discuss the direction in which the
phase shifts with the magnetic field. When the higher harmonic components of
the Aharonov-Bohm oscillations are negligible, the phaseshift is a
monotonically increasing function with respect to the source-drain bias
voltage. To observe the Aharonov-Bohm oscillations with higher visibility, we
need strong coupling between the quantum dots and the voltage probe. However,
this leads to dephasing since the voltage probe acts as a B\"{u}ttiker
dephasing probe. The interplay between such antithetic concepts provides a peak
in the visibility of the Aharonov-Bohm oscillations when the coupling between
the quantum dots and the voltage probe changes.Comment: 17 pages, 9 figures, accepted for publication in Physical Review
Nuclear spin relaxation rate of nonunitary Dirac and Weyl superconductors
Nonunitary superconductivity has attracted renewed interest as a novel
gapless phase of matter. In this study, we investigate the superconducting gap
structure of nonunitary odd-parity chiral pairing states in a superconductor
involving strong spin-orbit interactions. By applying a group theoretical
classification of chiral states in terms of discrete rotation symmetry, we
categorized all possible point-nodal gap structures in nonunitary chiral states
into four types in terms of the topological number of nodes and node positions
relative to the rotation axis. In addition to conventional Dirac and Weyl point
nodes, we identify a novel type of Dirac point node unique to nonunitary chiral
superconducting states. The node type can be identified experimentally based on
the temperature dependence of the nuclear magnetic resonance longitudinal
relaxation rate. The implication of our results for a nonunitary odd-parity
superconductor in UTe is also discussed.Comment: 18 pages, 4 figure
Divide-and-conquer verification method for noisy intermediate-scale quantum computation
Several noisy intermediate-scale quantum computations can be regarded as
logarithmic-depth quantum circuits on a sparse quantum computing chip, where
two-qubit gates can be directly applied on only some pairs of qubits. In this
paper, we propose a method to efficiently verify such noisy intermediate-scale
quantum computation. To this end, we first characterize small-scale quantum
operations with respect to the diamond norm. Then by using these characterized
quantum operations, we estimate the fidelity between an actual -qubit output state obtained from the noisy intermediate-scale quantum computation and the
ideal output state (i.e., the target state) . Although the
direct fidelity estimation method requires copies of on average, our method requires only copies even in the
worst case, where is the denseness of . For
logarithmic-depth quantum circuits on a sparse chip, is at most
, and thus is a polynomial in . By using the IBM
Manila 5-qubit chip, we also perform a proof-of-principle experiment to observe
the practical performance of our method.Comment: 17 pages, 7 figures, v3: Added a proof-of-principle experiment (Sec.
IV) and improved Sec. V, Accepted for publication in Quantu
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