9,542 research outputs found
Entangled single-wire NiTi material: a porous metal with tunable superelastic and shape memory properties
NiTi porous materials with unprecedented superelasticity and shape memory
were manufactured by self-entangling, compacting and heat treating NiTi wires.
The versatile processing route used here allows to produce entanglements of
either superelastic or ferroelastic wires with tunable mesostructures. Three
dimensional (3D) X-ray microtomography shows that the entanglement
mesostructure is homogeneous and isotropic. The thermomechanical compressive
behavior of the entanglements was studied using optical measurements of the
local strain field. At all relative densities investigated here ( 25 -
40), entanglements with superelastic wires exhibit remarkable macroscale
superelasticity, even after compressions up to 25, large damping capacity,
discrete memory effect and weak strain-rate and temperature dependencies.
Entanglements with ferroelastic wires resemble standard elastoplastic fibrous
systems with pronounced residual strain after unloading. However, a full
recovery is obtained by heating the samples, demonstrating a large shape memory
effect at least up to 16% strain.Comment: 31 pages, 10 figures, submitted to Acta Materiali
Compact Neural Networks based on the Multiscale Entanglement Renormalization Ansatz
This paper demonstrates a method for tensorizing neural networks based upon
an efficient way of approximating scale invariant quantum states, the
Multi-scale Entanglement Renormalization Ansatz (MERA). We employ MERA as a
replacement for the fully connected layers in a convolutional neural network
and test this implementation on the CIFAR-10 and CIFAR-100 datasets. The
proposed method outperforms factorization using tensor trains, providing
greater compression for the same level of accuracy and greater accuracy for the
same level of compression. We demonstrate MERA layers with 14000 times fewer
parameters and a reduction in accuracy of less than 1% compared to the
equivalent fully connected layers, scaling like O(N).Comment: 8 pages, 2 figure
Qubism: self-similar visualization of many-body wavefunctions
A visualization scheme for quantum many-body wavefunctions is described,
which we have termed qubism. Its main property is its recursivity: increasing
the number of qubits reflects in an increase in the image resolution. Thus, the
plots are typically fractal. As examples, we provide images for the ground
states of commonly used Hamiltonians in condensed matter and cold atom physics,
such as Heisenberg or ITF. Many features of the wavefunction, such as
magnetization, correlations and criticality, can be visualized as properties of
the images. In particular, factorizability can be easily spotted, and a way to
estimate the entanglement entropy from the image is provided
- …