February 13, 2012

Superconducting Josephson Junctions and their applications for ADC and DAC purposes.

Over the past 25 years we have seen the rise of a new science, the quantum. The amount of research in this field has been astounding, yet commercial and civilian applications of this new and exciting technology has been limited to MRI machines and GPR surveying. The quantum sciences and their associated technologies such as RSFQ, have yet to enter the mainstream, even as there status as "disruptive" technology has been clear for years. Quantum computing has been heralded as allowing "perfect" security, yet applications beyond data security seem far away, as mass production is not yet feasible.

It has been observed that Josephson Junction arrays exhibit 'perfect' voltage to frequency conversion, allowing the creation of perfect DAC's. By using this DAC as one of the building blocks of a Multiple-order delta-sigma ADC, allows incredibly accurate and high speed analog to digital conversion, sampling at high speeds in the gigahertz range. This technique of data capture is currently employed at CERN in Geneva, Switzerland, and allows unparalleled accuracy in data capture of experiments.

These same devices are in use by the NIST as the International Voltage Reference, where 1v has been defined as a perfect frequency derived from a superconducting tunnel junction array. By current definition roughly 72Ghz fed into a Superconducting Tunnel Junction outputs exactly 1v, unaffected by thermal cycling.

The use of these superconducting Josephson Junction devices has yet to reach commercial viability, yet it seems closer everyday. The fabrication of superconducting devices is now possible with "common" IC fabrication plants, and newer and higher temperature superconductors are found everyday. It's only a matter of time before this 'disruptive' technology truly disrupts our entire electronics and computer industry forever. Imagine computers capable of handling the data sets required for holograms, on the order of 10 terabytes a second! The promise of a perfect ADC and DAC has virtually infinite uses as well, again it's only time until capturing the raw neurological data feed of the electrochemical bio-computer of high level organisms such as humans will become a possibility, what this entails is the topic of science fiction.

This blog's goal is to spark broader interest in the real technologies being explored by the quantum sciences. For the most part most people think quantum physics and quantum science in general has no everyday purpose, except theoretical or purely mathematically, this blog hopes to destroy these prejudices, and explore the uses of these technologies for common people, students and researchers in other scientific fields. It might not be long before these technologies are as common and pervasive as the semiconducting technology used today.