Two from Caltech Elected to National Academy of Engineering

Two members of the Caltech community—professor Paul Dimotakis (BS '68, physics; MS '69, aeronautics; PhD '73, applied physics) and JPL scientist Adam Steltzner (MS '91, applied mechanics)—have been elected to the National Academy of Engineering (NAE), an honor considered among the highest professional distinctions awarded to an engineer. The academy welcomed 80 new members and 22 foreign members this year. In addition to Dimotakis and Steltzner, the new class of members includes five alumni, Emily A. Carter (PhD '87, chemistry), Arati Prabhakar (MS '80, electrical engineering; PhD '85, applied physics), Gabriel M. Rebeiz (MS '83, PhD '88, electrical engineering), Yongkui Sun (PhD '90, chemistry), and Stephen M. Trimberger (BS '77, engineering and applied science; PhD '83, computer science).

Paul Dimotakis is the John K. Northrop Professor of Aeronautics and professor of applied physics in the Division of Engineering and Applied Science, and a senior research scientist at JPL. He was recognized by the NAE for his contributions to the fluid mechanics of jet propulsion and other processes involving turbulence, mixing, and transport. He has most recently been conducting experimental, theoretical, and numerical investigations in supersonic-propulsion flows. Dimotakis served as JPL's chief technologist from 2006 to 2011 and has continued collaborating with JPL to estimate the vertical distribution of CO2 throughout the atmosphere using spaceborne instruments. He recently co-led a study between the Caltech campus, JPL, and others, with support by the Keck Institute for Space Studies, on the possibility of bringing a small asteroid into orbit around Earth or the moon.

Adam Steltzner is the chief engineer for the Mars 2020 project and the manager of the Planetary Entry, Descent, and Landing and Small Body Access Office at JPL. Steltzner was recognized for his work in the development of the Mars Curiosity rover's entry, descent, and landing system, and for contributions to the control of parachute dynamics. In addition to working on Curiosity, he has also contributed to the Galileo, Cassini, Mars Pathfinder, and Mars Exploration Rover missions.

The new members will be formally inducted at a ceremony during the NAE's Annual Meeting in Washington, D.C., on October 9, 2016.

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Monday, February 29, 2016

Modeling molecules at the microscale

Tiny Diatoms Boast Enormous Strength

Diatoms are single-celled algae organisms, around 30 to 100 millionths of a meter in diameter, that are ubiquitous throughout the oceans. These creatures are encased within a hard shell shaped like a wide, flattened cylinder—like a tambourine—that is made of silica. Researchers in the lab of Julia Greer, professor of materials science and mechanics in Caltech's Division of Engineering and Applied Science, have recently found that these shells have the highest specific strength—the strength at which a structure breaks with respect to its density—of any known biological material, including bone, antlers, and teeth. The findings have been published in the February 9 issue of Proceedings of the National Academy of Science.

The shell, or frustule, of a diatom is porous, perforated by a honeycomb-like pattern of holes. There are several theories about the function of these intricate shell designs, including that they evolved to control fluid flow, for example, or to help the organisms acquire nutrients. Greer and her group propose that the holes also act as stress concentrators—"flaws" in the material that can suppress the propagation of cracks, which would lead to failure of the entire organism.

"Silica is a strong but brittle material. For example, when you drop a piece of glass, it shatters," says Greer. "But architecting this material into the complex design of these diatom shells actually creates a structure that is resilient against damage. The presence of the holes delocalizes the concentrations of stress on the structure."

The group plans to use design principles from diatoms to create resilient, bioinspired artificial structures.

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Researchers have discovered that tiny diatom shells have the highest specific strength of any biological material.

Contemplating a Quantum Future

Last week, Caltech's Institute for Quantum Information and Matter (IQIM) honored the legacy and contributions of theoretical physicist Richard Feynman, marking 50 years since he received the Nobel Prize in Physics for his work on quantum electrodynamics. Feynman spent much of his career working to understand better the laws and implications of quantum mechanics—the rules that dictate the bizarre behavior of matter at the scale of individual atoms and particles. He foresaw how quantum mechanics could lead to the development of nanotechnology and even a quantum computer that could solve problems that would be intractable for conventional computers. Over two days, IQIM hosted two events to celebrate that vision by exploring the research and development currently underway at what might be called the quantum frontier.

The first event, "One Entangled Evening," aimed to delight, educate, and inspire an audience not only of scientists and engineers but also of artists, entertainers, and members of the public. Among the highlights of the evening were a video tribute to Feynman by Microsoft cofounder Bill Gates; a song and dance about quantum mechanics performed by artist Gia Mora and John Preskill, the Richard P. Feynman Professor of Theoretical Physics at Caltech and director of IQIM; and a screening of a short video titled Anyone Can Quantum, narrated by actor Keanu Reeves and featuring actor Paul Rudd playing a game of "quantum chess" with renowned physicist Stephen Hawking.

The following day, IQIM hosted an all-day Quantum Summit that brought together scientists and engineers from academia and industry to discuss progress in the quantum realm.

One session featured a panel discussion about the future of quantum computers with researchers from Google, HP Laboratories, IBM, Intel, the Institute for Quantum Computing, and Microsoft. Moderated by Jennifer Ouellette, senior science editor at Gizmodo.com, the discussion started with brief descriptions of the approach that each company or institute is taking in the quest for a quantum computer as well as answers to the questions, "Why quantum computing, and why now?"

Ray Beausoleil leads the Large-Scale Integrated Photonics research group at HP Laboratories. His team is currently trying to put thousands of nonlinear optical devices on a chip and to get them interacting coherently—in a way that their quantum properties are not disturbed by outside noise. As for his answer to the "Why quantum now?" question, "If you're a big computer company, you're looking at quantum computing because you know that, depending on your point of view … Moore's Law is in danger of being over," he explained. "So we have to start thinking more energetically about what computing will look like in 10 to 20 years."

"People have been saying that Moore's Law was over since about the time Richard Feynman proposed the quantum computer," countered Jim Clarke, manager of quantum hardware and novel memory research at Intel. Intel was cofounded by Gordon Moore (PhD '54), the originator of Moore's Law—the 1965 prediction that the amount of processing power, based on the number of transistors in a circuit, will double about every two years. "My take is Moore's Law is not ending," Clarke continued. "In fact, I think we need at least a couple more generations of Moore's Law just to be able to enable a large-scale quantum computer."

IBM Fellow Charles Bennett said that IBM is working to get a small number of superconducting qubits to work coherently and to understand what those qubits are doing. "That is a tremendous task, and we're putting a lot of effort into that," he said.

Parsa Bonderson, a theoretical physicist from Microsoft's Station Q at UC Santa Barbara, said that while Microsoft is keeping its eyes on a number of approaches, its main focus is on topological quantum computing, an idea devised in the 1990s by Alexei Kitaev, now the Ronald and Maxine Linde Professor of Theoretical Physics and Mathematics at Caltech. The approach attempts to develop much more stable qubits, known as topological qubits, that would be less sensitive to the disturbances that destroy the quantum properties of all other qubits. (Jason Alicea, professor of theoretical physics at Caltech, provided an overview of topological quantum computing in an earlier session at the summit.)

And why now? Bonderson answered, "We're starting to really feel like this could be within reach this time."

Google, for one, seems to agree. The company made headlines in 2013 when it bought a system from D-Wave Systems, a startup company that has built an early prototype of a limited quantum computer. Google's main goal, noted its director of engineering Hartmut Neven, is "to get a practical quantum computer as quickly as we can."

What can be done with a quantum computer? Krysta Svore, a senior researcher in Microsoft's Quantum Architectures and Computation Group, works to address that question and presented a number of potential answers in a morning session at the summit. Some of the ideas that reach beyond improving scientists' ability to study quantum systems include improving machine learning and simulating chemicals and chemical reactions more precisely in order to facilitate drug design and improving machine learning.

Ouellette asked the panelists what they thought might be possible with a small quantum computer, perhaps with 100 qubits.

Ray Laflamme, executive director of the Institute for Quantum Computing at the University of Waterloo, in Ontario, said he would use such a computer to help train students, postdocs, and young faculty "to think quantumly."

Intel's Clarke spoke about modeling the dynamics of molecules, including ozone and carbon dioxide, which are just out of reach of conventional computers. "Well, that's climate change, so that resonates with a lot of people," he said. "If you go even further, you get into the protein space. … Misfolded proteins are the genesis of so many diseases—cancer, multiple sclerosis, and others."

Microsoft's Bonderson suggested that a small quantum computer might be useful for designing a better quantum computer. And Bennett reminded everyone that the quantum computer would likely do more than simply provide more processing power. "It's not going to be the solution to the supposed problem of the demise of Moore's Law. It's going to change things in a way that is more interesting," he said. "It's like saying if we've got radio, how much better does that make things than if we just had the telegraph or we just had post offices?"

Beausoleil added that he would not let himself try to determine how the quantum computer should be used. Instead, he said, "I'd put it online as rapidly as possible and let people who are not physicists start experimenting."

And Google's Neven talked about the potential applications of a full-fledged quantum computer in the artificial intelligence (AI) field. Noting that formulating fundamental laws of physics is extremely difficult and something that only a tiny fraction of people can do, he said, "The question is: Is this really a task that, as physics develops further, remains a human task? Or is this, rather, a task that we should hand over to machines?"

He said that he believed that forms of artificial intelligence could prove to be better physicists and that quantum computing would be involved. "I would dare to conjecture that the most creative systems we will ever see will be quantum AI systems," he said.

During other sessions at the summit, John Martinis of Google spoke about quantum simulation with superconducting qubits; Oskar Painter, the John G. Braun Professor of Applied Physics at Caltech, presented on acoustic quantum transducers; and David Wineland, a Nobel laureate from National Institute of Standards and Technology, described the latest thinking on entangled trapped ions.

IQIM, which spans Caltech's Divisions of Physics, Mathematics and Astronomy and Engineering and Applied Science, is a Physics Frontiers Center supported by the National Science Foundation and by the Gordon and Betty Moore Foundation. 

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Contemplating a Quantum Future
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IQIM hosted a Quantum Summit that brought scientists and engineers together to discuss progress in the quantum realm.

Toward a Sustainable Society

The Dow Sustainability Innovation Student Challenge Award (SISCA) at Caltech honors students and scientists who have made significant contributions to finding sustainable solutions to the world's most pressing social, economic, and environmental problems. The award was established in 2009 by the Dow Chemical Company with the goal of promoting "forward thinking in social and environmental responsibility," according to the SISCA website. This year, graduate students Trevor Del Castillo and Niklas Thompson shared the $10,000 grand prize for their research developing a sustainable catalyst for nitrogen fixation.

Nitrogen is an abundant element crucial to many fertilizers and other chemicals produced on a large scale, but it must first be "fixed" from its inert gaseous state (N2) into usable reactive forms such as ammonia (NH3). The current leading process for synthesizing ammonia, the Haber-Bosch process, is expensive and energy-intense, requiring extreme temperatures and pressures (about 700 degrees Fahrenheit and 200 bars of pressure).

"From a human health perspective, fertilizer production is arguably the most important industrial chemical process that we practice," says Del Castillo. "We currently conduct this chemistry on a tremendous scale in order to feed approximately half of the global population. However, the current technology for fertilizer production is underpinned by high inputs and is hence typically practiced where fossil fuel sources are readily available and inexpensive. In addition to these energy constraints, current modes of agricultural fertilizer use are environmentally harmful and can be impractical in the developing world, where the demand for fertilizer will continue to increase moving forward."

New catalyst technologies have the potential to address this challenge. Del Castillo and Thompson—both graduate students in the laboratory of Jonas Peters, the Bren Professor of Chemistry and director of the Resnick Sustainability Institute—have studied a recently discovered catalyst system to drive nitrogen fixation, resulting in improved performance and furnishing mechanistic insights. Inspired by a family of enzymes that performs biological nitrogen fixation at room temperatures and pressures, the Peters lab has demonstrated that a simple iron compound can catalyze the fixation of nitrogen gas into ammonia at very low temperature and atmospheric pressure.

"This is a field where new technology and innovation has the potential to impact global social equity and sustainable food security while reducing environmental impact," Thompson says. "Our team's work is a small step in this context, but we ultimately hope our fundamental science discoveries will inspire more practical, sustainable technologies. In principle, nitrogen fixing catalysts can be coupled to artificial photosynthesis technologies, potentially opening the door to modular, accessible, and carbon-neutral fertilizer production."

The runners-up for the SISCA prize are Cody Finke, a graduate student, and Justin Jasper, a Resnick Sustainability Institute Prize Postdoctoral Scholar. Both work in the research group of Michael Hoffmann, the James Irvine Professor of Environmental Science, and together they have improved upon a design for a solar-powered wastewater treatment system created for toilets in the developing and developed world. Their process combines ultraviolet (UV) irradiation and electrochemical treatment to produce water suitable for reuse in agriculture and ecosystem services.

"We proposed a hybrid electrochemical-UV system that could be used to provide efficient wastewater treatment in places where water and sewer infrastructure are not available, such as parts of the developing world," Jasper says. "We were particularly excited about our research since it suggested that adding a UV step to the process significantly accelerated treatment and limited formation of disinfection byproducts that can be detrimental to human health.  Therefore, with further work, our system may be able to provide not only wastewater treatment, but also a water source for applications such as irrigation or household cleaning."

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Rosens Recharge Support for Bioengineering

Caltech board chair emeritus and longtime Compaq chairman Benjamin M. (Ben) Rosen (BS '54) and his wife, Donna, have made a bequest commitment to advance scientific exploration at the intersection of biology and engineering. It is anticipated that the couple's latest gift may double the endowment for the Donna and Benjamin M. Rosen Bioengineering Center.

Established in 2008 with $18 million from the Benjamin M. Rosen Family Foundation of New York, the Rosen Center has become a hub for research and educational initiatives that bring together applied physics, chemical engineering, synthetic biology, computer science, and more.

"Just as we had the digital revolution in the last century, we are having a biological sciences revolution in this century," Ben Rosen says. "And Caltech is the place to be."

Read more on the Caltech giving site.

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Rosens Recharge Support for Bioengineering
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Caltech board chair emeritus Ben Rosen (BS ’54) and his wife Donna have made a commitment to scientific exploration at the intersection of biology and engineering.

Rosakis Inducted into Academy of Athens

Ares Rosakis, Caltech's Theodore von Kármán Professor of Aeronautics and Mechanical Engineering in the Division of Engineering and Applied Science, has been inducted into the Academy of Athens as a Corresponding Member. The academy was founded in 1926 and is the highest research establishment in Greece, supporting the sciences, humanities, and fine arts.

"My election as a Corresponding Member to the Academy of Athens, in addition to the great scientific honor that it represents, also has a very special meaning for me as a Greek," says Rosakis—shown at right addressing the academy at his induction ceremony. "This is after all the leading scientific and cultural institution of my country of birth, and their recognition carries, for me, exceptional sentimental value."

Rosakis's research is interdisciplinary, covering the fields of aerospace, solid mechanics, mechanics of materials failure, and mechanics of earthquake seismology. He is a leading expert in the area of dynamic failure of solid materials. His address to the academy was titled "Representing Large Earthquakes in the Mechanics Laboratory: Identifying Characteristic Ground Shaking Signatures due to Supershear Ruptures."

Rosakis, a native of Greece, received bachelor's and master's degrees from Oxford University, and his PhD from Brown University. He joined the Caltech faculty in 1982 as the Institute's youngest tenure-track faculty member. He served as chair of the Division of Engineering and Applied Science from 2009 to 2015, and as director of the Graduate Aerospace Laboratories from 2004 to 2009.

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Innovations in the Air

Sure, Google's driverless car is pretty cool. But according to key leaders in the aerospace industry, much of the world's most innovative work is happening not in Silicon Valley but in the laboratories at their companies, where researchers are expanding the boundaries of everything from space travel to deep-sea exploration.

At the "Innovation in Aerospace" forum held at Caltech on Friday, January 22—part of the Idea 2 Innovation series cosponsored by Innovate Pasadena and Caltech—three of the aerospace industry's biggest companies discussed some of their most exciting new ventures. Northrop Grumman's Starshade project could help find life on other planets. Boeing's new unmanned Echo Seeker submarine is capable of diving 20,000 feet below sea level. Lockheed Martin's new imaging technology could radically shrink the size of space telescopes, making it far more efficient to send them deep into space.

Executives from each of the three companies, along with a representative from the start-up incubator Starburst Accelerator, were guided by moderator Andrea Belz (PhD '00), USC Marshall School of Business entrepreneur in residence, in a wide-ranging discussion about aerospace innovation and the quest to invent better models for fostering creative thinking—or, as several panelists put it, "being innovative in how we innovate"—as well as about the challenges of competing for talent with headline-grabbing companies like Google, Facebook, and Uber.

In addition, unlike those companies, innovators in aerospace work in a heavily regulated environment. And in the battle to attract attention and talent, the industry also faces this hurdle: it cannot discuss some of its most innovative work in public because it is often government-funded and top-secret.

That battle to attract and retain new and young talent, the forum's participants said, is critical, because the average age of the aerospace industry's engineers is increasing. Unlike in the days of the Apollo space missions, when much of the industry's workforce was in its 20s, today an estimated half of the industry's engineers are eligible for retirement within the next five years, according to panelist John Tracy, Boeing's chief technology officer.

"You've got to make sure that the next generation is going to come along that has the vision, that has the passion, that has the drive, and has the desire to create the future of aerospace," Tracy said.

The forum was held at Caltech's Cahill Center for Astronomy and Astrophysics; in addition to Boeing's Tracy, the panel included Scott Fouse, vice president of the Advance Technology Center at Lockheed Martin; Erik Antonsson, Northrop Grumman's corporate director of technology; and Starburst Accelerator cofounder Vandad Espahbodi.

Much of the discussion centered on ways in which the industry might foster creativity without getting in its way. The panelists acknowledged that large companies like Lockheed Martin, Northrop Grumman, and Boeing face this dilemma not only when nurturing talent internally but also when trying to partner with smaller start-up companies working on cutting-edge technologies.

"The trick is, if you touch the start-up at such a young, nascent stage, you will kill it, you will defeat its potential," Starburst's Espahbodi warned, adding that the goal thus becomes to find the right level of noninvasive partnership that will "help them succeed at arm's length."

The panelists disputed the notion that companies like theirs are too monolithic and bureaucratic to allow individual employees to innovate. Northrop Grumman's Antonsson, a former Caltech professor of mechanical engineering, noted that the company spends more than half a billion dollars annually on research and development.

These resources, he said, give the company freedom to experiment. In fact, Antonsson added, it was just this sort of experimentation by one of the company's small internal research groups that produced the Starshade, a technology that will help researchers look at planets dozens of light-years away—including those possibly hospitable to life—by using a space-traveling shade to block the light from stars near those planets.

Mory Gharib, Caltech's Hans W. Liepmann Professor of Aeronautics and Bioinspired Engineering, director of the Graduate Aerospace Laboratories, and vice provost, says he thought the forum underscored the vital importance of the industry. He notes that while Uber, for instance, is a revolutionary company, its disappearance would not have a particularly dramatic impact on Americans' lives. "But imagine if Boeing disappeared," says Gharib, who delivered opening remarks at the forum.

Guruswami (Ravi) Ravichandran, Caltech's John E. Goode, Jr., Professor of Aerospace and Mechanical Engineering and the Otis Booth Leadership Chair of the Division of Engineering and Applied Science, says the forum was "another example of the exciting and inspiring developments I have been observing in the Southern California aerospace industry over the past several years."

As Ravichandran, who delivered closing remarks, says, the four panel members not only "have the expertise and the knowledge, but they're also able to inspire people through stories."

Written by Alex Roth

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Novel Calibration Tool Will Help Astronomers Look for Habitable Exoplanets

Promising new calibration tools, called laser frequency combs, could allow astronomers to take a major step in discovering and characterizing earthlike planets around other stars. These devices generate evenly spaced lines of light, much like the teeth on a comb for styling hair or the tick marks on a ruler—hence their nickname of "optical rulers." The tick marks serve as stable reference points when making precision measurements such as those of the small shifts in starlight caused by planets pulling gravitationally on their parent stars.

Yet today's commercially available combs have a significant drawback. Because their tick marks are so finely spaced, the light output of these combs must be filtered to produce useful reference lines. This extra step adds complexity to the system and requires costly additional equipment.

To resolve these kinds of issues, Caltech researchers looked to a kind of comb not previously deployed for astronomy. The novel comb produces easily resolvable lines, without any need for filtering. Furthermore, the Caltech comb is built from off-the-shelf components developed by the telecommunications industry.

"We have demonstrated an alternative approach that is simple, reliable, and relatively inexpensive," says paper coauthor Kerry Vahala, the Ted and Ginger Jenkins Professor of Information Science and Technology and Applied Physics as well as the executive officer for Applied Physics and Materials Science in Caltech's Division of Engineering and Applied Science. The kind of frequency comb used by the researchers previously has been studied in the Vahala group in a different application, the generation of high-stability microwaves.

"We believe members of the astronomical community could greatly benefit in their exoplanet hunting and characterization studies with this new laser frequency comb instrument," says Xu Yi, a graduate student in Vahala's lab and the lead author of a paper describing the work published in the January 27, 2016, issue of the journal Nature Communications.

Scientists first began widely using laser frequency combs as precision rulers in the late 1990s in fields like metrology and spectroscopy; for their work, the technology's developers (John L. Hall of JILA and the National Institute of Standards and Technology (NIST) and Theodor Hänsch of the Max Planck Institute of Quantum Optics and Ludwig Maximilians University Munich) were awarded half of the Nobel Prize in Physics in 2005. In astronomy, the combs are starting to be utilized in the radial velocity, or "wobble" method, the earliest and among the most successful methods for identifying exoplanets.

The "wobble" refers to the periodic changes in a star's motion, accompanied by starlight shifts owing to the Doppler effect, that are induced by the gravitational pull of an exoplanet orbiting around the star. The magnitude of the shift in the starlight's wavelength—on the order of quadrillionths of a meter—together with the period of the wobble can be used to determine an exoplanet's mass and orbital distance from its star. These details are critical for assessing habitability parameters such as surface temperature and the eccentricity of the exoplanet's orbit. With exoplanets that pass directly in front of (or "transit") their host star, allowing their radius to be determined directly, it is even possible to determine the bulk composition—for example, if the planet is built up primarily of gas, ice, or rock. 

In recent years, so-called mode-locked laser combs have proven useful in this task. These lasers generate a periodic stream of ultrashort light pulses to create the comb. With such combs, however, approximately 49 out of every 50 tick marks must be blocked out. This requires temperature- and vibration-insensitive filtering equipment.

The new electro-optical comb that Vahala and his team studied relies on microwave modulation of a continuous laser source, rather than a pulsed laser. It produces comb lines spaced by tens of gigahertz. These lines have from 10 to 100 times wider spacing than the tick marks of pulsed laser combs.

To see how well a prototype would work in the field, the researchers took their comb to Mauna Kea in Hawaii. In September 2014, the instrument was tested at the NASA Infrared Telescope Facility (IRTF); in March 2015, it was tested with the Near Infrared Spectrometer on the W. M. Keck Observatory's Keck II telescope with the assistance of UCLA astronomer Mike Fitzgerald (BS '00) and UCLA graduate student Emily Martin, coauthors on the paper. The researchers found that their simplified comb (the entire electro-optical comb apparatus requires only half of the space available on a standard 19-inch instrumentation rack) provided steady calibration at room temperature for more than five days at IRTF. The comb also operated flawlessly during the second test—despite having been disassembled, stored for six months, and reassembled.

"From a technological maturity point of view, the frequency comb we have developed is already basically ready to go and could be installed at many telescopes," says paper coauthor Scott Diddams of NIST.

The Caltech comb produces spectral lines in the infrared, making it ideal for studying red dwarf stars, the most common stars in the Milky Way. Red dwarf stars are brightest in infrared wavelengths. Because red dwarfs are small, cool, and dim, planets orbiting these types of stars are easier to detect and analyze than those orbiting hotter sun-like stars. NASA's Kepler space observatory has shown that almost all red dwarf stars host planets in the range of one to four times the size of Earth, with up to 25 percent of these planets located in the temperate, or "habitable," zone around their host stars. Thus, many astronomers predict that red dwarfs provide the best chance for the first discovery of a world capable of supporting life.

"Our goal is to make these laser frequency combs simple and sturdy enough that you can slap them onto every telescope, and you don't have to think about them anymore," says paper coauthor Charles Beichman, senior faculty associate in astronomy and the executive director of the NASA ExoPlanet Science Institute at Caltech. "Having these combs routinely available as a modest add-on to current and future instrumentation really will expand our ability to find potentially habitable planets, particularly around very cool red dwarf stars," he says.

The research team is planning to double the frequency of the prototype comb's light output—now centered around 1,550 nanometers, in the infrared—to reach into the visible light range. Doing so would allow the comb also to calibrate spectra from sun-like stars, whose light output is at shorter, visible wavelengths, and thus seek out planets that are Earth's "twins."

Other authors of the paper are Jiang Li, a visitor in applied physics and materials science, graduate students Peter Gao and Michael Bottom, and scientific research assistant Elise Furlan, all from Caltech; Stephanie Leifer, Jagmit Sandhu, Gautam Vasisht, and Pin Chen of JPL; Peter Plavchan (BS '01), formerly at Caltech and now a professor at Missouri State University; G. Ycas of NIST; Jonathan Gagne of the University of Montréal; and Greg Doppmann of the Keck Observatory.

The paper is titled "Demonstration of a near-IR line-referenced electro-optical laser frequency comb for precision radial velocity measurements in astronomy." The research performed at Caltech and JPL was funded through the President's and Director's Fund Program, and the work at NIST was funded by the National Science Foundation. 

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Adam Hadhazy
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Novel Tool Aids Exoplanet Hunt
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Researchers have developed a laser frequency comb that expands the ability to find habitable worlds.
Friday, January 29, 2016
Center for Student Services 360 (Workshop Space) – Center for Student Services

Course Ombudsperson Training, Winter 2016

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