New Optical Clock
Promises More Accuracy than Cesium.
NIST researchers have demonstrated a new
kind of atomic clock that has the potential to be up to 1,000 times more
accurate than today’s best clock. The new clock is based on an energy
transition in a single trapped mercury ion (a mercury atom that is missing one
electron). Building a clock based on such a high-frequency transition was
previously impractical because it requires both “capturing” the ion and holding
it very still to get accurate readings, and having a mechanism that can “count”
the ticks accurately at such a high frequency.
The quality of a clock depends on its stability and accuracy—whether the clock provides a constant, unchanging output frequency, and how close the measured frequency is to the fundamental atomic resonance that provides the clock’s “tick.” One advantage of the new clock is that it ticks much faster. Today’s international time and frequency standards, such as NIST-F1, measure an atomic resonance of about 9 billion cycles per second. By contrast, the new NIST device monitors an optical frequency more than 100,000 times higher or about 1 quadrillion (US) cycles per second.
The quality of a clock depends on its stability and accuracy—whether the clock provides a constant, unchanging output frequency, and how close the measured frequency is to the fundamental atomic resonance that provides the clock’s “tick.” One advantage of the new clock is that it ticks much faster. Today’s international time and frequency standards, such as NIST-F1, measure an atomic resonance of about 9 billion cycles per second. By contrast, the new NIST device monitors an optical frequency more than 100,000 times higher or about 1 quadrillion (US) cycles per second.
And my follow up email (which still seems like a good idea to me) -
The Arithmetic Muse strikes...
I've just been musing
over that Quadrillion Hz clock a bit, and I knew straight off you'd want me to
share my musings ;-)
Basically in
US-speak, 'illions (I just made that word up) are 1000 * 1000 ^ prefix.
So,
Mono (1) gives 1000 * 1000 ^ 1 = Million,
Bi (2) gives 1000 * 1000 ^ 2 = Billion,
Tri (3) gives 1000 * 1000 ^ 3= Trillion,
Quad (4, should be Tetra to stay
Greek, I think) gives 1000 * 1000 ^ 4 = Quadrillion.
By the same logic,
Zero (0) gives 1000 * 1000 ^ 0 = the famous 'Zillion'
In which case, at a mere 1000, it
isn't so huge after all :-)
I propose we stick
with the classical languages and call Zero 'Null', therefore 1000 is a
'Nillion' which fits 'Nil' too.
Today, we have this -
Nuke clock incapable of losing time chimes with boffins
Precise to 1/20th of a sec in 14bn years
By Anna Leach The force that binds neutrons to an atom's nucleus could be used to
create clocks that are 100 times more accurate than today's best atomic
clocks, say physicists at the University of New South Wales (UNSW).The nuclear clock outlined in a paper accepted for publication in Physics Letters Review would neither lose nor gain 1/20th of a second in 14 billion years, the age of the universe.
The unprecedented accuracy of this new time-keeping comes from
linking the system to the orbit of a neutron within an atomic nucleus.
That makes it more accurate than atomic clocks, explains Professor
Victor Flambaum, Head of Theoretical Physics at UNSW.
Atomic clocks use the orbiting electrons of an atom as the clock pendulum. But we have shown that by using lasers to orient the electrons in a very specific way, one can use the orbiting neutron of an atomic nucleus as the clock pendulum, making a so-called nuclear clock with unparalleled accuracy....
Well, they have a theory, now they just have to figure out how to actually make such a clock!