Storing a growing flood of data forever demands better solutions.

A new analysis proves that all integer programs theoretically could be solved much faster than previously guaranteed.

Novel designs reduce the hardware overhead for error correction in simulations.

Researchers use computers to show that equations can "blow up."

Finding novel materials needs more than pure machine learning.

Cryptographers seek algorithms quantum computers cannot break.

Quantum computation has a long road ahead.

Architectures suited for molecules streamline the identification of pharmaceutical candidates.

Ideas for quantum computing change the way we think about space and time.

Kernel methods clarify why neural networks generalize so well.

Combining neural networks with symbolic representations might make them more versatile and dependable.

Two-dimensional materials---graphene and its cousins---could enable better integrated circuits.

Japan tops the Top500 supercomputer rankings, for the moment.

The uncanny power of machine learning can be turned against it.

A theorem about computations that exploit quantum mechanics challenges longstanding ideas in mathematics and physics.

Errors and biases in artificial intelligence systems often reflect the data used to train them.

Formulating a decades-old geometric conjecture as a satisfiability problem opened the door to its final resolution.

The long-standing goal of providing artificial intelligence some measure of common sense remains elusive.

We report the fabrication of modulation doped Si/Gex Si1−x heterostructures by molecular beam epitaxy. The samples are characterized by Rutherford backscattering spectrometry, cross-sectional transmission electron microscopy, electron beam induced current, Hall measurement, and the magnetoresistance (Shubnikov-de Haas) measurements. Threading dislocation densities of = 106cm−2 are observed for relaxed Ge0.3Si0.7 films on Si (100). The modulation doped structures fabricated on these Ge0.3 Si0.7 films contain two-dimensional electron gases with mobilities ranging from 60,000 to 96,000 cm2/V - s at 4.2 K.