102 research outputs found
Superconducting transmon qubit-resonator quantum baterry
Quantum battery (QB) is the miniature energy storage and release device and
plays a crucial role in future quantum technology. Here, an implementation
scheme of a QB is proposed on a superconducting circuit which is composed by
coupled transmon qubits and a one-dimensional transmission line resonator.
We derive the Hamiltonian of the QB system and investigate its charging
performance by considering three decay channels. We find that the presence of
the decay channels suppresses the high oscillation of the energy storage
process, thereby realizing a stable and powerful QB. In particular, compared
with the resonator decay and the qubit relaxation, the qubit dephasing shows a
counterintuitive advantage in our QB. We show that the nearest neighbor
interaction always have a positive impact on the stable energy and the coupling
only significantly influences the maximum charging power in the fully
nondegenerate ground state region. We also demonstrate the feasibility of our
approach by evaluating the QB performance under experimental parameters.Comment: 8 pages, 6 figure
Cavity-Heisenberg spin chain quantum battery
We propose a cavity-Heisenberg spin chain (CHS) quantum battery (QB) with the
long-range interactions and investigate its charging process. The performance
of the CHS QB is substantially improved compared to the Heisenberg spin chain
(HS) QB. When the number of spins , the quantum advantage of
the QB's maximum charging power can be obtained, which approximately satisfies
a superlinear scaling relation . For the CHS QB,
can reach and even exceed , while the HS QB can only reach about
. We find that the maximum stored energy of the CHS QB has a
critical phenomenon. By analyzing the Wigner function, von Neumann entropy, and
logarithmic negativity, we demonstrate that entanglement can be a necessary
ingredient for QB to store more energy, but not sufficient
Three-level Dicke quantum battery
Quantum battery (QB) is the energy storage and extraction device that is
governed by the principles of quantum mechanics. Here we propose a three-level
Dicke QB and investigate its charging process by considering three quantum
optical states: a Fock state, a coherent state, and a squeezed state. The
performance of the QB in a coherent state is substantially improved compared to
a Fock and squeezed states. We find that the locked energy is positively
related to the entanglement between the charger and the battery, and
diminishing the entanglement leads to the enhancement of the ergotropy. We
demonstrate the QB system is asymptotically free as . The
stored energy becomes fully extractable when , and the charging power
follows the consistent behavior as the stored energy, independent of the
initial state of the charger.Comment: 9 Pages, 9 Figure
Closed-loop three-level charged quantum battery
Quantum batteries are energy storage or extract devices in a quantum system.
Here, we present a closed-loop quantum battery by utilizing a closed-loop
three-state quantum system in which the population dynamics depends on the
three control fields and associated phases. We investigate the charging process
of the closed-loop three-level quantum battery. The charging performance is
greatly improved due to existence of the third field in the system to form a
closed-contour interaction. Through selecting an appropriate the third control
field, the maximum average power can be increased, even far beyond the most
ideal maximum power value of non-closed-loop three-level quantum battery
(corresponding to the most powerful charging obtainable with minimum quantum
speed limit time and the maximum charging energy). We study the effect of
global driving-field phase on the charging process and find the maximum
extractable work (`ergotropy') and charging power vary periodically under
different control field, with a period of . Possible experimental
implementation in nitrogen-vacancy spin is discussed
Adiabatic light propagation in nonlinear waveguide couplers with longitudinally varying detunings via resonance-locked inverse engineering
We investigate the adiabatic evolution of light in nonlinear waveguide
couplers via resonance-locked inverse engineering based on stimulated Raman
adiabatic passage (STIRAP). The longitudinal varying detunings of the
propagation coefficients are designed to eliminate dynamically the nonlinear
effect, which induce the non-adiabatic oscillations. We show that different
light evolutions such as complete light transfer, light split and light return
can be realized adiabatically with appropriate choices of the detunings even in
the nonlinear regime. The features open new opportunities for the realization
of all-optical nonlinear devices with high fidelity in integrated optics.Comment: 8 pages,6 figure
Analytically solvable many-body Rosen-Zener quantum battery
Quantum batteries are energy storage devices that satisfy quantum mechanical
principles. How to obtain analytical solutions for quantum battery systems and
achieve a full charging is a crucial element of the quantum battery. Here, we
investigate the Rosen-Zener quantum battery with two-level systems, which
includes atomic interactions and external driving field. The analytical
solutions of the stored energy, changing power, energy quantum fluctuations,
and von Neumann entropy are derived by employing the gauge transformation. We
demonstrate that full charging process can be achieved when the external
driving field strength and scanning period conforms to a quantitative
relationship. The local maximum value of the final stored energy corresponds to
the local minimum values of the final energy fluctuations and von Neumann
entropy. Moreover, we find that the atomic interaction induces the quantum
phase transition and the maximum stored energy of the quantum battery reaches
the maximum value near the quantum phase transition point. Our result provides
an insightful theoretical scheme to realize the efficient quantum battery.Comment: 9 pages,7 figure
(Methanolato)(pyridine)[N 2,N 2′-(pyridine-2,6-diyldicarbonyl)diacetohydrazide(2–)]iron(III) methanol solvate
In the title complex, [Fe(C11H10N5O4)(CH3O)(C5H5N)]·CH4O, the FeIII ion has a distorted pentagonal-bipyramidal geometry. In the crystal structure, molecules are linked into one-dimensional chains along [1
] via intermolecular O—H⋯O and N—H⋯O hydrogen bonds
Polypropylene filled with glass spheres in extrusion-based additive manufacturing : effect of filler size and printing chamber temperature
High-fidelity superadiabatic population transfer of a two-level system with a linearly chirped Gaussian pulse
We investigate high-fidelity superadiabatic quantum driving in a chirped Gaussian two-level model with a Gaussian temporal envelope and a linear detuning. We show that the nonadiabatic losses can be canceled to any desired order by constructing and adjusting an auxiliary Hamiltonian (counter-diabatic field) and a symmetry in the fidelity arises on the counter-diabatic field ratio. A high-fidelity, robust, and accelerated (in a shorter time) transitionless superadiabatic population transfer is achieved that ensures a perfect following of the instantaneous adiabatic ground state even in the nonadiabatic regime. The features make the superadiabatic protocol a potentially important tool for quantum information
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