Superlattice
A superlattice is a periodic structure of layers of two (or more) materials. Typically, the thickness of one layer is several nanometers. It can also refer to a lower-dimensional structure such as an array of quantum dots or quantum wires.
Discovery
Superlattices were discovered early in 1925 by Johansson and Linde after the studies on gold-copper and palladium-copper systems through their special X-ray diffraction patterns. Further experimental observations and theoretical modifications on the field were done by Bradley and Jay, Gorsky, Borelius, Dehlinger and Graf, Bragg and Williams and Bethe. Theories were based on the transition of arrangement atoms in crystal lattices from disordered state to an ordered state.
Mechanical properties
J.S. Koehler theoretically predicted that by using alternate (nano-)layers of materials with high and low elastic constants, shearing resistance is improved by up to 100 times as the Frank-Read source of dislocations cannot operate in the nanolayers.
Podcasts:
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by Lights
Siberia
by: LightsFrom the busy parks, to the icy tides.
Someday we'll decide where we want to live out our lives.
Formalities sparked, tumbling along.
Keeping the heat on even though summer's come and gone.
I would sail across the east sea, just to see you on the far side.
Where the wind is cold and angry, there you'll be to take me inside.
We'll find ways to fill the empty, far from all the hysteria.
I don't care if we suddenly find ourselves in Siberia.
Siberia
Inside a street car, or on a mountain trail.
Details, details,
You breathe in when I exhale.
No matter where we are, or which way the wind blows.
Or how heavy the snow, nothing can change where we will go.
I would sail across the east sea, just to see you on the far side.
Where the wind is cold and angry, there you'll be to take me inside.
We'll find ways to fill the empty, far from all the hysteria.
I don't care if we suddenly find ourselves in Siberia.
Siberia,
We'll leave Canada, for Siberia.
Siberia, Siberia, Siberia, Siberia, Siberia...
I would sail across the east sea, just to see you on the far side.
Where the wind is cold and angry, there you'll be to take me inside.
We'll find ways to fill the empty, far from all the hysteria.
I don't care if we suddenly find ourselves in Siberia.
Siberia,