11,777 research outputs found
Quantum Simulator for Transport Phenomena in Fluid Flows
Transport phenomena still stand as one of the most challenging problems in
computational physics. By exploiting the analogies between Dirac and lattice
Boltzmann equations, we develop a quantum simulator based on pseudospin-boson
quantum systems, which is suitable for encoding fluid dynamics transport
phenomena within a lattice kinetic formalism. It is shown that both the
streaming and collision processes of lattice Boltzmann dynamics can be
implemented with controlled quantum operations, using a heralded quantum
protocol to encode non-unitary scattering processes. The proposed simulator is
amenable to realization in controlled quantum platforms, such as ion-trap
quantum computers or circuit quantum electrodynamics processors.Comment: 8 pages, 3 figure
Setting up tunneling conditions by means of Bohmian mechanics
Usually tunneling is established after imposing some matching conditions on
the (time-independent) wave function and its first derivative at the boundaries
of a barrier. Here an alternative scheme is proposed to determine tunneling and
estimate transmission probabilities in time-dependent problems, which takes
advantage of the trajectory picture provided by Bohmian mechanics. From this
theory a general functional expression for the transmission probability in
terms of the system initial state can be reached. This expression is used here
to analyze tunneling properties and estimate transmissions in the case of
initial Gaussian wave packets colliding with ramp-like barriers.Comment: 18 pages, 4 figure
Effect of ancilla's structure on quantum error correction using the 7-qubit Calderbank-Shor-Steane code
In this work we discuss the ability of different types of ancillas to control
the decoherence of a qubit interacting with an environment. The error is
introduced into the numerical simulation via a depolarizing isotropic channel.
After the correction we calculate the fidelity as a quality criterion for the
qubit recovered. We observe that a recovery method with a three-qubit ancilla
provides reasonable good results bearing in mind its economy. If we want to go
further, we have to use fault-tolerant ancillas with a high degree of
parallelism, even if this condition implies introducing new ancilla
verification qubits.Comment: 24 pages, 10 Figures included. Accepted in Phys. Rev. A 200
- …