Two of the most intriguing scientific fields of the 20th century have come together to revolutionize the 21st signifying the marriage of quantum physics and computing theory, according to the National Institute of Standards and Technology. NIST has contributed much to its early research and development and is helping to shape its future.
Not surprisingly, the rules of quantum physics are difficult to comprehend because they are so different from how we interact daily with objects and see the world.
In our everyday world, objects appear to move in a continuous, predictable pattern. For example, water rises steadily in a bathtub and a rocket soars smoothly into the sky. But in the quantum world, objects jump and jitter. An electron bound to the center of an atom can instantly leap from one orbit to another, essentially disappearing from the original orbit and reappearing in another.
This quantization of energy in electrons and other particles can be very useful for encoding information in the binary digit system of 0s and 1s that computers use to process data. A lower-energy state of an atom can represent a 0 and a higher-energy state can be a 1.
Things get really peculiar, though, when you add in another quantum rule called superposition, according to NIST in an article, “The Strange World of Quantum Physics.”
Superpositions are very fragile; an accidental noise can alter the superpositions, leading to errors that can be tricky to correct. Measuring an ion — or otherwise disturbing it — destroys the superposition, forcing the ion to be in a 0 or 1 state, and it acts like an ordinary bit. Destroying superpositions is called decoherence, and it’s a big problem. So, researchers must protect qubits, and isolate them.
Another characteristic of quantum computing is entanglement, and it’s perhaps the strangest quantum property of them all, according to NIST physicists. It’s a sort of quantum marriage between qubits. Imagine you have an ion acting as a qubit, and it’s in a superposition of 0 and 1, and you entangle it with a second ion, also 0 and 1. The two entangled ions are going to maintain a special relationship, even if they are separated by large distances and are completely isolated from one another.
NIST had a jump start in quantum information in the 1990s. NIST scientists and mathematicians were already using qubits — but under a different name — atomic clocks. In short, the field of quantum research developed with NIST researchers working with atoms in a certain way that would improve the precision of atomic clocks.
Atomic clocks tell time with astonishing precision. The NIST-F2, the most accurate U.S. atomic clock used for timekeeping, keeps time to an accuracy of less than a millionth of a billionth of a second. GPS satellites that contain atomic clocks depend on such precision to send time-stamped signals that help us pinpoint our locations anywhere on Earth to within about a meter.
The NIST ion lab has been advancing atomic clock research since the 1970s. By looking at these early physics experiments from a different perspective, NIST and JILA labs scientists developed the study of quantum information. They inspired quantum information innovations from the very beginning, according to an article on the NIST website that traces the history of quantum physics.
JILA was founded in 1962 as a joint institute of the University of Colorado Boulder and the National Institute of Standards and Technology. Research topics range from the small, frigid world governed by the laws of quantum mechanics through the physics of biological and chemical systems to the processes that shape the stars and galaxies, according to the JILA website.
If quantum theory sounds like science fiction, don’t worry, NIST is trying to simplify the concepts for non-scientists, like you and me, because researchers expect quantum physics will completely revolutionize information technology and computing as we know it.
NIST has set up a webpage featuring the history and future of quantum physics, topics of study include:
–Introduction: A New Quantum Revolution
–The Strange World of Quantum Physics
–Quantum Logic Gates
–The Race to Build a Quantum Computer
–Cryptography in the Quantum Age
Even though researchers still aren’t sure what kinds of discoveries they will make with quantum information science or what the most useful applications will be; they are quite sure that the outcomes will have a significant impact on national security and the economy. The U.S. recognizes that stakes are high — from nations to corporations, everyone is getting into the game.
The global race is on.
As a non-regulatory agency of the Commerce Department, NIST promotes U.S. innovation and industrial competitiveness by advancing measurement science, standards and technology in ways that enhance economic security and improve our quality of life. For more information, visit www.nist.gov.