Using a convenient and flexible method for creating twin light beams, researchers from the National Institute of Standards and Technology (NIST) and the University of Maryland (UM) have produced “quantum images,” pairs of information-rich visual patterns whose features are “entangled,” or inextricably linked by the laws of quantum physics.
In addition to promising better detection of faint objects and improved amplification and positioning of light beams, the researchers’ technique for producing quantum images—unprecedented in its simplicity, versatility, and efficiency—may someday be useful for storing patterns of data in quantum computers and transmitting large amounts of highly secure encrypted information. The research performed at the NIST/UM Joint Quantum Institute (JQI) was described in the June 12 edition of Science Express.*
Conventional photographic films or digital camera sensors only record the color and intensity of a light wave striking their surfaces. A hologram additionally records a light wave’s “phase”—the timing the crests and valleys in the wave. However, much more happens in a light wave. Even the most stable laser beam brightens and dims randomly over time because light has inherent quantum level “uncertainties” in its properties. Controlling these fluctuations—which represent a sort of “noise”—can improve detection of faint objects, produce better amplified images and allow workers to more accurately position laser beams. Researchers can’t completely eliminate the noise, but they can rearrange it to improve desired features in images. A quantum-mechanical technique called “squeezing” lets physicists reduce noise in one property—such as intensity—at the expense of increasing the noise in a complementary property, such as phase. In addition to noise reduction, the quantum manipulations open new applications for images—such as transferring heaps of encrypted data protected by the laws of quantum mechanics and performing parallel processing of information for quantum computers.
The quantum images produced by the JQI team are in “entangled” pairs, transmitted by two light beams originating from the same point. Look at one quantum image, and it displays random and unpredictable changes over time. Look at the other image, and it exhibits very similar random fluctuations at the same time, even if the two images are far apart and unable to transmit information to one another. Together, they are squeezed: Matching up both quantum images and subtracting their fluctuations, their noise is lower—and their information content potentially higher—than it is from any two classical images. Each image is made of up to 100 distinct regions, akin to the pixels forming a digital image, each with its own independent optical and noise properties. A pixel on one image forms a partnership with a pixel on the other image—one could predict many of the properties in the second pixel just by looking at the first.
Previous efforts at making quantum images have been limited to building them up with “photon counting”—collecting one photon at a time over a long period of time—or having very specialized “images” such as something that could only be constructed from a dot and a ring. In contrast, the new method produces an entire image at one time and can make a wide variety of images in any shape. A next goal for the researchers is to produce quantum images with slowed-down light; such slowed images could be used in information storage and processing as well as communications applications.
Source: NIST
Related stories:
Scientists take the sharpest image ever made with light
(PhysOrg.com) -- A team of scientists from the Technische Universität Dresden (Germany) and the ESRF in Grenoble (France) has produced the image of an object at the highest resolution ever achieved with X-ray light. A 100-nanometre gold particle fixed on a substrate was reconstructed with 5 nanometre resolution. Contrary to other techniques, X-ray imaging works also in real-life environments like chemical processing or in the presence of high magnetic fields. The team reports its findings in the newest issue of
Phys. Rev. Lett. dated 5 September 2008 (published online 29 August 2008).
Quantum Chaos Unveiled?
(PhysOrg.com) -- A University of Utah study is shedding light on an important, unsolved physics problem: the relationship between chaos theory - which is based on 300-year-old Newtonian physics - and the modern theory of quantum mechanics.
New Technique Reveals Hidden Properties of Ultracold Atomic Gases
(PhysOrg.com) -- Physicists at JILA, a joint institute of the National Institute of Standards and Technology and the University of Colorado at Boulder, have demonstrated a powerful new technique that reveals hidden properties of ultracold atomic gases.
New paper offers insights into 'blinking' phenomena
A new paper by a team of researchers led by University of Notre Dame physicist Bolizsár Jankó provides an overview of research into one of the few remaining unsolved problems of quantum mechanics.
Physicists Store Images in Vapor
Books are written on solid pieces of paper for an obvious reason: the atoms in a solid don’t move around much, keeping the words and pictures in place for centuries. Trying to store letters and images in a gas medium, on the other hand, seems a little far-fetched. Atoms in a gas are constantly moving around, which would move the images around with them.
Ultrafast look into atoms and molecules
New record in ultrafast metrology: Physicists at Max-Planck Institute of Quantum Optics and the Ludwig-Maximilians-University Munich are the first to produce light pulses lasting only 80 attoseconds.
Physicists produce quantum-entangled images
Using a convenient and flexible method for creating twin light beams, researchers at the Joint Quantum Institute of the Commerce Department's National Institute of Standards and Technology and the University of Maryland have produced "quantum images," pairs of information-rich visual patterns whose features are "entangled," or inextricably linked by the laws of quantum physics. In addition to promising better detection of faint objects and improved amplification and positioning of light beams, the researchers' technique for producing quantum images—unprecedented in its simplicity, versatility, and efficiency—may someday be useful for storing patterns of data in quantum computers and transmitting large amounts of highly secure encrypted information. The research team, led by JQI's Paul Lett, describes the work in the June 12 edition of
Science Express.
Scientists discover exotic quantum state of matter
A team of scientists from Princeton University has found that one of the most intriguing phenomena in condensed-matter physics -- known as the quantum Hall effect -- can occur in nature in a way that no one has ever before seen.
