Latest Photon Stories

2011-04-20 08:45:25

Mercury's Exosphere: A Brief Overview One of the primary science goals of MESSENGER is to study Mercury's very thin atmosphere, or exosphere. Although observations of the exosphere from orbit have begun, these data must be carefully calibrated, and analysis is still underway. In the meantime, here is a primer on Mercury's exosphere: what it is, how we observe it, and why it is important. What Is Mercury's Exosphere? Mercury's atmosphere is so tenuous that the atoms or molecules comprising it...

2011-03-17 20:12:00

A team of researchers has integrated tiny detectors capable of counting individual photons on computer chips. These detectors, called "single-photon avalanche diodes (SPAD)," act like mini Geiger counters, producing a "tick" each time a photon is detected. The researchers present their findings in Applied Physics Letters, a journal published by the American Institute of Physics. "In the past, making these detectors required specialized processes, but recently there has been tremendous...

2011-03-17 12:02:59

A team of physicists in the United Kingdom has taken a giant step toward realizing efficient single-photon sources, which are expected to enable much-coveted completely secure optical communications, also known as "quantum cryptography." The team presents its findings in Applied Physics Letters, a journal published by the American Institute of Physics. Fluorescent "defect centers" in diamond act like atomic-scale light sources and are trapped in a transparent material that's large enough to...

2011-03-17 00:02:04

Scientists at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley have learned to control the quantum pathways determining how light scatters in graphene. Controlled scattering provides a new tool for the study of this unique material "“ graphene is a single sheet of carbon just one atom thick "“ and may point to practical applications for controlling light and electronic states in graphene nanodevices....

2011-03-10 18:27:56

New switching device could help build a dream: the ultrafast quantum Internet Northwestern University researchers have developed a new switching device that takes quantum communication to a new level. The device is a practical step toward creating a network that takes advantage of the mysterious and powerful world of quantum mechanics. The researchers can route quantum bits, or entangled particles of light, at very high speeds along a shared network of fiber-optic cable without losing the...

2011-03-10 13:43:37

Device may help process information and measure motion at quantum scale Physicists at the National Institute of Standards and Technology (NIST) have demonstrated an electromechanical circuit in which microwaves communicate with a vibrating mechanical component 1,000 times more vigorously than ever achieved before in similar experiments. The microscopic apparatus is a new tool for processing information and potentially could control the motion of a relatively large object at the smallest...

2011-02-28 10:22:31

Nanometer-scale gold particles are currently intensively investigated for possible applications in catalysis, sensing, photonics, biolabeling, drug carriers and molecular electronics Nanometer-scale gold particles are currently intensively investigated for possible applications in catalysis, sensing, photonics, biolabeling, drug carriers and molecular electronics. The particles are prepared in a solution from gold salts and their reactive gold cores can be stabilized with various organic...

2011-02-24 17:38:04

Like snowflakes or fingerprints, no two quantum dots are identical. But a new etching method for shaping and positioning these semiconductor nanocrystals might change that. What's more, tests at the National Institute of Standards and Technology (NIST) confirm that etched quantum dots emit single particles of light (photons), boosting prospects for powering new types of devices for quantum communications. The conventional way to build quantum dots"”at NIST and elsewhere"”is to...

2011-02-14 10:20:00

The fabric of space-time around spinning black holes should impart a "twist" in the property of light called orbital angular momentum. This momentum which could be detected here on Earth, the researchers say, may provide the first unique signature of black holes, reports the journal Nature Physics. Light particles , or photons, carry two kinds of momentum but only one of them is familiar. "If we take the Earth as an example, it spins around its own axis in about 24 hours - that is its spin...

2011-02-01 09:20:16

Inspired by the popular confidence trick known as "shell game," researchers at UC Santa Barbara have demonstrated the ability to hide and shuffle "quantum-mechanical peas" "“"“ microwave single photons "“"“ under and between three microwave resonators, or "quantized shells." In a paper published in the Jan. 30 issue of the journal Nature Physics, UCSB researchers show the first demonstration of the coherent control of a multi-resonator architecture. This topic has been...

Latest Photon Reference Libraries

2004-10-19 04:45:41

Electromagnetic Spectrum -- The electromagnetic spectrum describes the various types of electromagnetic radiation based on their wavelengths. Radio, representing wavelengths from a few feet to well over a mile, is at one end of the spectrum. Gamma ray radiation is at the other end: the wavelength of the harder types is so short, in the subatomic range, that we do not have instruments capable of directly measuring it. While the above classification scheme is generally accurate, in...

2004-10-19 04:45:41

Electromagnetic Radiation -- Electromagnetic radiation is a combination of oscillating electric and magnetic fields propagating through space and carrying energy from one place to another. Light is a form of electromagnetic radiation. The theoretical study of electromagnetic radiation is called electrodynamics, a subfield of electromagnetism. When any wire (or other conducting object such as an antenna) conducts alternating current, electromagnetic radiation is propagated at the same...

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Word of the Day
  • The offense of persistently instigating lawsuits, typically groundless ones.
  • An unlawful breach of duty on the part of a ship's master or crew resulting in injury to the ship's owner.
  • Sale or purchase of positions in church or state.
This word ultimately comes from the Old French word 'barater,' to cheat.