194,801 research outputs found
A Case for Redundant Arrays of Hybrid Disks (RAHD)
Hybrid Hard Disk Drive was originally concepted by Samsung, which incorporates a Flash memory in a magnetic disk. The combined ultra-high-density benefits of magnetic storage and the low-power and fast read access of NAND technology inspires us to construct Redundant Arrays of Hybrid Disks (RAHD) to offer a possible alternative to today’s Redundant Arrays of Independent Disks (RAIDs) and/or Massive Arrays of Idle Disks (MAIDs). We first design an internal management system (including Energy-Efficient Control) for hybrid disks. Three traces collected from real systems as well as a synthetic trace are then used to evaluate the RAHD arrays. The trace-driven experimental results show: in the high speed mode, a RAHD outplays the purely-magnetic-disk-based RAIDs by a factor of 2.4–4; in the energy-efficient mode, a RAHD4/5 can save up to 89% of energy at little performance degradationPeer reviewe
Giant Magnetoelastic Effects in BaTiO3-based Extrinsic Multiferroic Hybrids
Extrinsic multiferroic hybrid structures consisting of ferromagnetic and
ferroelectric layers elastically coupled to each other are promising due to
their robust magnetoelectric effects even at room temperature. For a
quantitative analysis of these magnetoelectric effects, a detailed knowledge of
the piezoelectric and magnetoelastic behavior of both constituents as well as
their mutual elastic coupling is mandatory. We here report on a theoretical and
experimental study of the magnetic behavior of BaTiO3-based extrinsic
multiferroic structures. An excellent agreement between molecular dynamics
simulations and the experiments was found for Fe50Co50/BaTiO3 and Ni/BaTiO3
hybrid structures. This demonstrates that the magnetic behavior of extrinsic
multiferroic hybrid structures can be determined by means of ab-initio
calculations, allowing for the design of novel multiferroic hybrids
The Magnetic Distortion Calibration System of the LHCb RICH1 Detector
The LHCb RICH1 detector uses hybrid photon detectors (HPDs) as its optical
sensors. A calibration system has been constructed to provide corrections for
distortions that are primarily due to external magnetic fields. We describe
here the system design, construction, operation and performance.Comment: 9 pages, 14 figure
Quantum probe and design for a chemical compass with magnetic nanostructures
Magnetic fields as weak as Earth's may affect the outcome of certain
photochemical reactions that go through a radical pair intermediate. When the
reaction environment is anisotropic, this phenomenon can form the basis of a
chemical compass and has been proposed as a mechanism for animal
magnetoreception. Here, we demonstrate how to optimize the design of a chemical
compass with a much better directional sensitivity simply by a gradient field,
e.g. from a magnetic nanostructure. We propose an experimental test of these
predictions, and suggest design principles for a hybrid metallic-organic
chemical compass. In addition to the practical interest in designing a
biomimetic weak magnetic field sensor, our result shows that gradient fields
can server as powerful tools to probe spin correlations in radical pair
reactions.Comment: 8 pages, 6 figures, comments are welcom
Design of Adiabatic MTJ-CMOS Hybrid Circuits
Low-power designs are a necessity with the increasing demand of portable
devices which are battery operated. In many of such devices the operational
speed is not as important as battery life. Logic-in-memory structures using
nano-devices and adiabatic designs are two methods to reduce the static and
dynamic power consumption respectively. Magnetic tunnel junction (MTJ) is an
emerging technology which has many advantages when used in logic-in-memory
structures in conjunction with CMOS. In this paper, we introduce a novel
adiabatic hybrid MTJ/CMOS structure which is used to design AND/NAND, XOR/XNOR
and 1-bit full adder circuits. We simulate the designs using HSPICE with 32nm
CMOS technology and compared it with a non-adiabatic hybrid MTJ/CMOS circuits.
The proposed adiabatic MTJ/CMOS full adder design has more than 7 times lower
power consumtion compared to the previous MTJ/CMOS full adder
Resonant spin-dependent electron coupling in a III-V/II-VI heterovalent double quantum well
We report on design, fabrication, and magnetooptical studies of a III-V/II-VI
hybrid structure containing a GaAs/AlGaAs/ZnSe/ZnCdMnSe double quantum well
(QW). The structure design allows one to tune the QW levels into the resonance,
thus facilitating penetration of the electron wave function from the diluted
magnetic semiconductor ZnCdMnSe QW into the nonmagnetic GaAs QW and vice versa.
Magneto-photoluminescence studies demonstrate level anticrossing and strong
intermixing resulting in a drastic renormalization of the electron effective g
factor, in perfect agreement with the energy level calculations.Comment: 4 pages, 5 Postscript figures, uses revtex
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