Researchers at the University of Surrey's Advanced Technology Institute manipulated zinc oxide, producing nanowires from this readily available material to create a ultra-violet light detector which is 10,000 times more sensitive to UV light than a traditional zinc oxide detector. Currently, photoelectric smoke sensors detect larger smoke particles found in dense smoke, but are not as sensitive to small particles of smoke from rapidly burning fires. Researchers believe that this new material could increase sensitivity and allow the sensor to detect distinct particles emitted at the early stages of fires, paving the way for specialist sensors that can be deployed in a number of applications. "UV light detectors made from zinc oxide have been used widely for some time but we have taken the material a step further to massively increase its performance. Essentially, we transformed zinc oxide from a flat film to a structure with bristle-like nanowires, increasing surface area and therefore increasing sensitivity and reaction speed," said Professor Ravi Silva, co-author of the study (, "On-chip Fabrication of High Performance Nanostructured ZnO UV Detectors") and head of the Advanced Technology Institute. The team predict that the applications for this material could be far reaching. From fire and gas detection to air pollution monitoring, they believe the sensor could also be incorporated into personal electronic devices, such as phones and tablets, to increase speed, with a response time 1000 times faster than traditional zinc oxide detectors. "This is a great example of a bespoke, designer nanomaterial that is adaptable to personal needs, yet still affordable. Due to the way in which this material is manufactured, it is ideally suited for use in future flexible electronics, a hugely exciting area," added Professor Silva.
Improved fire detection with new ultra-sensitive, ultraviolet light nanowire sensor
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Improving energy efficiency one atom at a time
Paul Simmonds looks at his molecular beam epitaxy (MBE) system the way other guys do a candy apple red Porsche. The sci-fi looking machine used to design and create new materials at the atomic level lights his eyes with pure joy. MBE is a cutting-edge technique that allows for the design and creation of completely new materials that don’t exist in nature. By creating extreme vacuum and temperature conditions, the instrument forces atoms to combine into unique nanoscale crystal layers. By adding additional layers of designer crystals, new materials can be created with specific or unusual properties. 
Paul Simmonds at his molecular beam epitaxy (MBE) system. Simmonds, a Cambridge graduate, came to Boise State in October from University of California, Los Angeles, where he managed the Integrated NanoMaterials Lab. Before that, he spent time as a post doc at Yale. He now is an assistant professor in both the Department of Physics and the Department of Materials Science and Engineering. A key negotiation during the interview process was his ability to purchase an MBE system for his Boise State lab. While he didn’t get a brand spanking new model, which costs more than a million dollars, he did find one that had been used by the Air Force and affiliates and he has been refurbishing and customizing it in his lab in the Multipurpose Classroom Building. While there still is a lot of work to be done to get it fully up and running, it will be a valuable new resource available to Boise State faculty and students and to industry members who want to collaborate with Simmonds in their research. “MBE enables us to control the properties of new crystals with exquisite precision, right down to the atomic level,” Simmonds said. “We can grow nanomaterials with features just a few billionths of a meter across, and even control how many electrons they have inside them.” In a nutshell, here’s how it works. The machine is a bit like an atomic spray painter. Various “arms” are loaded with elements like germanium or aluminum, which are then beamed as atoms onto a substrate surface in a vacuum chamber. The atoms on the surface eventually sort themselves into a pattern, and continue to do so until a solid surface is formed. A new layer is then started and the process repeats itself until, sometimes many hours later, the final product is achieved. “The strength of this is that it’s so versatile,” Simmonds said. “You can make all kinds of materials — metals, oxide materials, semiconductors …” The process also controls for the purity of the material. There are faster methods, but they cannot compete with the material, quality, resolution and control offered by MBE. Simmonds plans to build on previous research he did on a family of semiconductor nanostructures called III-V quantum dots. Quantum dots are useful for turning light into electricity, or electricity into light. His first project will use this technology to create a new kind of device to harvest waste heat and turn it into useful electricity. An example of waste heat would be a power station that loses a percentage of its heat energy generated by gas, coal or nuclear power. “If we can capture this heat that is otherwise lost and turn it into electricity using our devices, then the overall efficiency of the power station goes up significantly,” he said. He is currently seeking grants to fund this line of research. Simmonds said MBE systems are used in labs all over the world to push back the boundaries of physics, materials science, electrical engineering, chemistry and more. “The number of things they can do is huge,” he said, “and they are highly interdisciplinary.” The molecular beam epitaxy system is expected to be fully functional later this semester. To explore collaborating on a project using the MBE system, contact Simmonds at paulsimmonds@boisestate.edu or 426-3787.
Paul Simmonds at his molecular beam epitaxy (MBE) system. Simmonds, a Cambridge graduate, came to Boise State in October from University of California, Los Angeles, where he managed the Integrated NanoMaterials Lab. Before that, he spent time as a post doc at Yale. He now is an assistant professor in both the Department of Physics and the Department of Materials Science and Engineering. A key negotiation during the interview process was his ability to purchase an MBE system for his Boise State lab. While he didn’t get a brand spanking new model, which costs more than a million dollars, he did find one that had been used by the Air Force and affiliates and he has been refurbishing and customizing it in his lab in the Multipurpose Classroom Building. While there still is a lot of work to be done to get it fully up and running, it will be a valuable new resource available to Boise State faculty and students and to industry members who want to collaborate with Simmonds in their research. “MBE enables us to control the properties of new crystals with exquisite precision, right down to the atomic level,” Simmonds said. “We can grow nanomaterials with features just a few billionths of a meter across, and even control how many electrons they have inside them.” In a nutshell, here’s how it works. The machine is a bit like an atomic spray painter. Various “arms” are loaded with elements like germanium or aluminum, which are then beamed as atoms onto a substrate surface in a vacuum chamber. The atoms on the surface eventually sort themselves into a pattern, and continue to do so until a solid surface is formed. A new layer is then started and the process repeats itself until, sometimes many hours later, the final product is achieved. “The strength of this is that it’s so versatile,” Simmonds said. “You can make all kinds of materials — metals, oxide materials, semiconductors …” The process also controls for the purity of the material. There are faster methods, but they cannot compete with the material, quality, resolution and control offered by MBE. Simmonds plans to build on previous research he did on a family of semiconductor nanostructures called III-V quantum dots. Quantum dots are useful for turning light into electricity, or electricity into light. His first project will use this technology to create a new kind of device to harvest waste heat and turn it into useful electricity. An example of waste heat would be a power station that loses a percentage of its heat energy generated by gas, coal or nuclear power. “If we can capture this heat that is otherwise lost and turn it into electricity using our devices, then the overall efficiency of the power station goes up significantly,” he said. He is currently seeking grants to fund this line of research. Simmonds said MBE systems are used in labs all over the world to push back the boundaries of physics, materials science, electrical engineering, chemistry and more. “The number of things they can do is huge,” he said, “and they are highly interdisciplinary.” The molecular beam epitaxy system is expected to be fully functional later this semester. To explore collaborating on a project using the MBE system, contact Simmonds at paulsimmonds@boisestate.edu or 426-3787.Quantum glue
Even a perfect vacuum is not truly empty. If you could observe that vacuum on the quantum, atomic or subatomic scale, you would see a “bubbling soup” of "ghost" particles. Known as “virtual particles,” they randomly pop in and out of existence in the empty space; and they cause a phenomenon known as vacuum fluctuation. So, in a space that is completely devoid of any detectable radiation – that is, a vacuum existing at the temperature of absolute- zero – fluctuations in electromagnetic fields will still be taking place on a microscopic, quantum scale. Though they are called virtual, these particles create real forces between atoms. If you place two atoms close together, they will change the local vacuum between them, creating fluctuations through virtual photons – light particles. The attraction between these close-together atoms is called the van der Waals force. Place the atoms farther apart, and you will still observe a slight pull between them. This is the Casimir force. Both of these forces are weak and often hard to measure. Prof. Gershon Kurizki and research student Ephraim Shahmoon, of the Weizmann Institute’s Chemical Physics Department, together with Dr. Igor Mazets of the Vienna University of Technology recently suggested a way of enormously enhancing these forces – until they become a sort of “quantum glue” holding atoms together. In their paper, recently published in the ("Giant vacuum forces via transmission lines"), the researchers considered atoms placed near a line of conducting material, similar to an ordinary coaxial cable used to hook a TV to a satellite dish. In the setup they envision, a virtual photon that is emitted from one atom would be confined so that it propagates in one dimension to the nearest atom down the line, where it would be absorbed, then reemitted back to the first atom and so on. 
Possible "quantum glue" setup: Coaxial line: two concentric metallic cylinders, the inner one with radius a and the outer (hollow) one with radius b. Two dipoles represented by black circles are placed in between the cylinders, along the wave propagation direction z. They interact via modes of the coaxial line that are in the vacuum state, giving rise to a vdW-like interaction energy. Having this exchange of virtual photons occur under one-dimensional confinement, rather than in everyday three-dimensional space, greatly increases the odds that the process will take place. The researchers’ calculations suggest that the attraction between atoms via virtual photons in the electric coaxial cable could be millions of times greater than that in three-dimensional space, transforming a normally weak force into potent " glue." This research was highlighted in the journals and ("Giant Casimir effect"). If scientists manage to demonstrate such one-dimensional vacuum forces, their experiments could help us understand the phenomena surrounding virtual particles.
Possible "quantum glue" setup: Coaxial line: two concentric metallic cylinders, the inner one with radius a and the outer (hollow) one with radius b. Two dipoles represented by black circles are placed in between the cylinders, along the wave propagation direction z. They interact via modes of the coaxial line that are in the vacuum state, giving rise to a vdW-like interaction energy. Having this exchange of virtual photons occur under one-dimensional confinement, rather than in everyday three-dimensional space, greatly increases the odds that the process will take place. The researchers’ calculations suggest that the attraction between atoms via virtual photons in the electric coaxial cable could be millions of times greater than that in three-dimensional space, transforming a normally weak force into potent " glue." This research was highlighted in the journals and ("Giant Casimir effect"). If scientists manage to demonstrate such one-dimensional vacuum forces, their experiments could help us understand the phenomena surrounding virtual particles.
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