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The concept of temperature is critical in describing many physical phenomena, such as the transition from one phase of matter to another.  Turn the temperature knob and interesting things can happen.  But other knobs might be just as important for studying some phenomena.  One such knob is chemical potential, a thermodynamic parameter first introduced in the nineteenth century by scientists ...

Two physical phenomena, localization and ergodicity-breaking, are conjoined in new experimental and theoretical work.  Before we consider possible implications for fundamental physics and for prospective quantum computing, let’s first look at these two topics in turn.  It will bear providing some specific examples before getting to the quantum details.

 LOCALIZATION

When electrons pass through a material they encounter various degrees ...

From NIST-PML — Precise measurements of optical power enable activities from fiber-optic communications to laser manufacturing and biomedical imaging — anything requiring a reliable source of light. This situation calls for light-measuring (radiometric) standards that can operate over a wide range of power levels.

Currently, however, different methods for calibrating optical power measurements are required for different light levels. At high ...

From NIST-PML--JQI scientists have achieved a major milestone in simulating the dynamics of condensed-matter systems – such as the behavior of charged particles in semiconductors and other materials – through manipulation of carefully controlled quantum-mechanical models.

Going beyond their pioneering experiments in 2009 (the creation of “artificial magnetism”), the team has created a model system in which electrically neutral ...