6,853 research outputs found
Permafrost sequences on Kurungnakh Island, Lena Delta (NE Siberia, Russia) as key site of the late Quaternary environmental history of West Beringia
Cluster state generation using van der Waals and dipole-dipole interactions in optical lattices
We present a scalable method for generation of a cluster state for
measurement-based quantum computing using van der Waals or dipole-dipole
interactions between neutral atoms or polar molecules in an optical lattice.
Nearest neighbor entanglement is accomplished by performing a phase gate using
interaction of atoms in Rydberg states or molecules in large dipole moment
states. All nearest neighbors are sequentially entangled in a finite number of
operations, independent of the number of qubits, producing a 1D cluster state.
A universal 2D cluster state can be generated in several ms in a
two-dimensional optical lattice by producing a series of 1D cluster states in
one lattice direction, followed by application of the entangling operations in
another lattice direction. We discuss the viability of the scheme with Rb
Rydberg atoms.Comment: Revised and expanded versio
Pairing state in multicomponent superconductors
We use the microscopic weak coupling theory to predict the pairing state in
superconductors of cubic, hexagonal, or tetragonal symmetry, where the order
parameter is multicomponent, i.e., transforms according to either a
2-dimensional or a 3-dimensional representation of the crystal point group. We
show that the superconducting phase usually breaks the time-reversal symmetry
for singlet multicomponent superconductors. The superconducting order parameter
for triplet superconductors in most cases turns out to be non-magnetic.Comment: 7 page
Rydberg atom mediated polar molecule interactions: a tool for molecular-state conditional quantum gates and individual addressability
We study the possibility to use interaction between a polar molecule in the
ground electronic and vibrational state and a Rydberg atom to construct
two-qubit gates between molecular qubits and to coherently control molecular
states. A polar molecule within the electron orbit in a Rydberg atom can either
shift the Rydberg state, or form Rydberg molecule. Both the atomic shift and
the Rydberg molecule states depend on the initial internal state of the polar
molecule, resulting in molecular state dependent van der Waals or dipole-dipole
interaction between Rydberg atoms. Rydberg atoms mediated interaction between
polar molecules can be enhanced up to times. We describe how the
coupling between a polar molecule and a Rydberg atom can be applied to coherent
control of molecular states, specifically, to individual addressing of
molecules in an optical lattice and non-destructive readout of molecular
qubits
On Graph-Theoretic Identifications of Adinkras, Supersymmetry Representations and Superfields
In this paper we discuss off-shell representations of N-extended
supersymmetry in one dimension, ie, N-extended supersymmetric quantum
mechanics, and following earlier work on the subject codify them in terms of
certain graphs, called Adinkras. This framework provides a method of generating
all Adinkras with the same topology, and so also all the corresponding
irreducible supersymmetric multiplets. We develop some graph theoretic
techniques to understand these diagrams in terms of a relatively small amount
of information, namely, at what heights various vertices of the graph should be
"hung".
We then show how Adinkras that are the graphs of N-dimensional cubes can be
obtained as the Adinkra for superfields satisfying constraints that involve
superderivatives. This dramatically widens the range of supermultiplets that
can be described using the superspace formalism and organizes them. Other
topologies for Adinkras are possible, and we show that it is reasonable that
these are also the result of constraining superfields using superderivatives.
The family of Adinkras with an N-cubical topology, and so also the sequence
of corresponding irreducible supersymmetric multiplets, are arranged in a
cyclical sequence called the main sequence. We produce the N=1 and N=2 main
sequences in detail, and indicate some aspects of the situation for higher N.Comment: LaTeX, 58 pages, 52 illustrations in color; minor typos correcte
Engineering chiral spin interactions with Rydberg atoms
We propose to simulate the anisotropic and chiral Dzyaloshinskii-Moriya (DM)
interaction with Rydberg atom arrays. The DM Hamiltonian is engineered in a
one-dimensional optical lattice or trap array with effective long-range Rydberg
spins, interacting indirectly via a mobile mediator Rydberg atom. A host of XXZ
and DM Hamiltonians can be simulated with out-of-phase sign periodic coupling
strengths; for initial states in a stationary condensate, the DM interaction
vanishes. This theory allows for determination of the DM interaction (DMI)
vector components from first principles. The inherent anisotropy of the
Rydberg-Rydberg interactions, facilitates the DMI coupling to be tuned so as to
be comparable to the XXZ interaction. Our results make plausible the formation
of non-trivial topological spin textures with Rydberg atom arrays.Comment: 4 pages, 2 figure
Application of Microsecond Voltage Pulses for Water Disinfection by Diaphragm Electric Discharge
The paper presents the dependence of copper and silver ions formation on the duration of voltage pulses of diaphragm electric discharge and on the pH of treated liquid medium. Knowing it allows one to create an automatic control system to control bactericidal agent's parameters obtained in diaphragm electric discharge reactor. The current-voltage characteristic of the reactor with a horizontal to the diaphragm membrane water flow powered from the author`s custom pulse voltage source is also presented. The results of studies of the power consumption of diaphragm electric discharge depending on temperature of the treated liquid medium are given
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