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Science Technology

Laser Clock Generates One Trillion BPS 33

FunkyELF writes "Professor of optics, electrical and computer engineering and physics Peter Delfyett, Jr., of the School of Optics CREOL, has developed a laser-driven clock that is smaller than the head of a pin, with applications in computers as well as general timekeeping. One of many fascinating things going on at The University of Central Florida"
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Laser Clock Generates One Trillion BPS

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  • Nice, (Score:5, Funny)

    by Trusty Penfold ( 615679 ) <jon_edwards@spanners4us.com> on Monday October 28, 2002 @10:01PM (#4553061) Journal

    but I bet it still manages to fuck up daylight savings time.
    • by Anonymous Coward
      How do they know it's a TRILLION BPS? We all know that Floridan's can't count worth shit...
      • I bet they don't even know what a trillion is...

        trillion [dictionary.com]

        In Britain, France, and Germany, 10^18 or a million cubed.

        In the USA and Canada, 10^12.

        Hell, the word comes from 'tri' for third power, and million. Quite how the americans decided to make a trillion as a million to the power of two is beyond the rest of the world....

        that's my rant for the day :)

        Out.
        • Well, a million is 1,000,000 x 1000^0
          a billion is is 1,000,000 x 1000^1
          and a trillion is 1,000,000 x 1000^2

          So a trillion is the third in the series of 1,000,000 x 1000^n.

          Listen, I love the metric system, and as an American, I wish we'd adopt it officially. But I don't see how your nomenclature for numbers is any better. What do *you* call 10^12? A million million? Sorry, I like our system better. Or even if you call it a thousand billion, it still doesn't fit.

          Our number system puts a comma after every three digits, starting from the right side. So if you see a number that starts off like this: 100,000,000.... You'll know it's a hundred something, whether it's a hundred million, billion, trillion or quadrillion. If you're going to call 1,000,000,000,000 (10^12) "A thousand billion", instead of "one [n-illion]" then you confuse the whole system.
          • 10^12 is called a billion for most of the world.

            We could both equally call it a million million.

            You could call it a thousand billion or a trillion.

            I guess the only thing that would start to confuse everyone is if I started talking about numbers like:

            987,654,321,234,567,890

            nine hundred and eighty seven thousand six hundred and fifty four billion, three hundred and twenty one thousand, two hundred and thirty four million, five hundred and sixty seven thousand eight hundred and ninety.

            Which I guess you'd call:

            nine hundred and eighty seven quadrillion six hundred and fifty four trillion, three hundred and twenty one billion, two hundred and thirty four million, five hundred and sixty seven thousand, eight hundred and ninety.

            The systems screwy. I blame the americans.
      • by Anonymous Coward
        They watch interference patterns. There are mathematical ways to measure infinitesimaly small pulses as long as they repeat in a predictable pattern. Essentialy, they have written a mathematical proof that the device which they built resonates at 1 THz.
  • by 3-State Bit ( 225583 ) on Monday October 28, 2002 @10:06PM (#4553082)
    Then you can't bloody well read it, can you?
    I have a clock that by definition is more accurate.
    It consists of a cesium atom.
  • This is way more impressive than the last contribution made by (former) UCF Students... The Blair Witch Project [yahoo.com]
    • That is students or, in this case, faculty
    • There are enough good teams from Florida!

      UCF is an excellent school. I'm really impressed everytime I hear something about the students/teachers it's good. That being said OU has the highest percentage of Merit Scholor's (sp? since I'm not one!) of a Public University in the country! Although with $15k/year scholorship cash and costs at only 3k/semester for classes & books, I wish I were, then my student loans would be nonexistant!
  • NY Times Story (Score:5, Informative)

    by infernow ( 529374 ) on Monday October 28, 2002 @10:25PM (#4553154) Homepage
    There's a link of for this story on the NY times at the bottom of the page.
    I figure i'd post it here for reference:
    And here it is. [nytimes.com]
  • by Anonymous Coward on Monday October 28, 2002 @10:52PM (#4553248)
    I mean, I know this is cruel and all, but I saw the professor's picture [ucf.edu], and the first thing I thought of was that sticker on the side of the laser...

    DO NOT LOOK INTO LASER WITH REMAINING GOOD EYE.

    I'm sorry! I even went to UCF for a while!
  • by Nyphur ( 514992 ) <nyphur@gmail.com> on Tuesday October 29, 2002 @08:29AM (#4555049) Homepage
    When reading up on the atomic clock on this site, I read mention aobut the mercury ion clock which would be, when finished, 1000 times more accurate than the standard caesium atomic clock: http://whyfiles.org/078time/2.html [whyfiles.org]

    More competition for the new laser-clock, but at 1008 Billion signals per second, I see a major advantage in his laser-research.

    Peter Delfyett's area of focus is "increasing the speed of fiber-optic systems" because, according to his research, in the current fibre-optic system:

    "beams from several separate lasers, each costing about $1,000, send light wavelengths at the same speed at the same time down the line and the total speed is calculated by multiplying the number of wavelengths by their pulse rates."

    Delfyette's current area of research led him to use a "mode-lock laser". This is used to "control the timing and the number of wavelengths that are simultaneously generated"

    If you can't see where I'm going with this, think about fibre-optic communications, particularly Fibre-Optic Broadband. This new system can generate 1008 Billion signals per second, each signal having the ability to carry one digital bit, and all this from just one laser, instead of many expensive, bulky convergance lasers. The implications of Peter's new laser-research include the fact that if you had a single fibre-optic fibre for broadband internet access, it would give you a maximum download speed of 120162.9638671875 Megabytes per second, unless I'm mistaken which I could be because my mathematics isn't the best. At any rate, it's much faster than today's fibre-optic broadband connections. Also, since the fibre-optic lines themselves need not be changed, only new laser-systems installed, this technology could be implemented into all current major fibre-optic networks.

    I can see Peter's research coming in very handy in the future of land-based communications.
  • by BMagneton ( 128886 ) on Tuesday October 29, 2002 @01:07PM (#4557254)
    I work for a group that uses and researches mode-locked lasers for a different purpose, and there seem to be a few inaccuracies and misconceptions floating around.

    Mode locked lasers have been around since at least 1970, and are widely used for laser and communications research and telecom applications. It's a technology that's getting better as people like Delfyett iron out the substantial kinks, but it's hardly a new technique.

    Talking about the size of these things, let's trace a source or two. UCF News release: "smaller than the head of a pin." NY Times: "that potentially could nestle on the head of a pin." Really, the individual optical components (Mach-Zehnder modulator, fiber, electronic oscillator, waveplates, filters, polarization control, isolators, etc.) reqired for a mode locked laser are each at least a few cubic centimeters. With good packaging, you might get a mode locked laser into a lunchbox, but no way as small as a pinhead. That's not to say thirty years down the road they won't have figured out how to put all of these components onto a chip and make it tiny, but it's not happening any time in the next ten years without a serious revolution in optics miniturization.

    Mode locked lasers utility as a clock is limited to very fast things, as they're not good clocks for long periods of time. The numerical measure that is quoted for clock accuracy (-140 dBc/Hz, for those of you that follow the stuff) isn't good for time periods longer than 0.1 microseconds. Go below 1-10 MHz (more than 1 - 0.1 microseconds worth of time) or so, and the inaccuracy goes up exponentially for any mode locked laser. Now, that's a thousand clock ticks for a GHz processor, so it's fine for chip clocks. Just don't try timing anything that takes a millisecond.

    Compare this to atomic clocks, which get worse over these short time scales, but much, much better over any human time scale. There are physics-based reasons for this, mostly involving the temperature, vibration, and other nusiance noises applied to a few very simple atoms suspended in a shielded vacum trap vs the stability of a bunch of optical components in a box that constantly have optical and electrical power flowing through them.

    This is why NIST is looking at linking the two types of clock, not replacing one with the other.

    BMagneton
  • "After seeing this, the scientists are still looking frantically through the motherboard manual that controls the light to find out what exactly the POST code is for one trillion beats in a second"

    And if nothing better comes out of this, at least we know we can hook the driver circuit up to a speaker to scare the hell out of any insect in a 4 mile radius.

Programmers do it bit by bit.

Working...