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In a new study published in Scientific Reports, JILA Fellow and University of Colorado Boulder physics professor Andreas Becker and his team theorized a new method to produce extreme ultraviolet (EUV) and x-ray light with elliptical polarization, a special shape in which the direction of light waves’ oscillation is changing. This method could provide experimentalists with a simple technique to generate such light, which is beneficial for physicists to further understand the interactions between electrons in materials on the quantum level, paving the way for designing better electronic devices such as circuit boards, solar panels, and more.

The JILA Physics Frontiers Center (PFC), an NSF-funded science center within JILA (a world-leading physics research institute), has recently been awarded a $25 million grant after a re-competition process.

This science center brings together 20 researchers across JILA to collaborate to realize precise measurements and cutting-edge manipulations to harness increasingly complex quantum systems. Since its establishment in 2006, the JILA PFC’s dedication to advancing quantum research and educating the next generation of scientists has helped it to stand out as the heart of JILA’s excellence.

JILA Fellow and University of Colorado Boulder��Distinguished Professor Andreas Becker has been awarded a 2023 fellowship to Optica (formerly the��Optical Society of America). Becker's work at JILA focuses on the analysis and simulation of ultrafast phenomena in atoms, molecules, and clusters, in particular attosecond electron dynamics, coherent control, and molecular imaging. Using special laser frequencies, Becker and his team are able to study the dynamics of these atoms and molecules in different time scales.

JILA Fellow Andreas Becker is one of the 11 University of Colorado Boulder faculty to be awarded a 2021 Distinguished Professor title. CU Distinguished Professors are tenured faculty members who give outstanding work in research or creative work and have a reputation of excellence in promoting learning and student engagement in the research process as well as dedicated to the profession, the university, and its affiliates.

Many physicists use lasers to study quantum mechanics, atomic and molecular physics��and nanophysics. While these lasers can be helpful in the research process, there are certain constraints for the researcher. According to JILA Fellow Andreas Becker: "For certain wavelengths of these laser pulses, such as deep ultraviolet, you may not know, or not be able to measure, the temporal profile." The temporal profile of a laser pulse is, however, important for researchers when analyzing data. "A lot of people cannot fully analyze their data, because they don't know the details of the pulse that was used to produce the data," said graduate student Spencer Walker. As a way to research this constraint, the Becker and Jaron-Becker laboratories collaborated to publish a paper in Optics Letters, suggesting a possible solution.

The process of creating spin-polarized electrons has been studied for some time but continues to surprise physicists. These types of electrons have their spin aligned in a specific direction. The probability of creating a spin-polarized electron from an atom tends to be rather small except in some very specific situations. Yet, in a new paper published in Physical Review A, JILA graduate student Spencer Walker, former graduate student Joel Venzke, and former undergraduate student Lucas Kolanz in the Becker Lab theorized a new way towards enhancing this probability through the use of ultrashort laser pulses and an electron’s so-called doorway states. These doorway states are excited states of an electron in an atom that is closest to its lowest energy state, the ground state.

Follow that electron! JILA researchers��have��proposed a means of capturing an electron's flight path during ionization, and in doing so, determining the state of the atom at that moment.

Three JILA Fellows have been named 2018 Fellows of the American Physical Society. The three new Fellows—Andreas Becker, Heather J. Lewandowski, and James K. Thompson—were��nominated from varying divisions of APS. Andreas Becker was nominated by the APS Division of Atomic, Molecular & Optical physics for his contributions to the understanding of the behavior of atoms and molecules in intense light fields, including seminal theoretical studies of attosecond dynamics, photoionization, complex electron dynamics in simple systems such as H2, and a better understanding of high-harmonic generation.

The photoelectric effect has been well known since the publication of Albert Einstein’s 1905 paper explaining that quantized particles of light can stimulate the emission of electrons from materials. The nature of this quantum mechanical effect is closely related to the question how much time it might take for an electron to leave a material such as a helium atom.

Mid-infrared (mid-IR) laser light is accomplishing some remarkable things at JILA. This relatively long-wavelength light (2–4 µm), when used to drive a process called high-harmonic generation, can produce bright beams of soft x-rays with all their punch packed into isolated ultrashort bursts. And, all this takes place in a tabletop-size apparatus. The soft x-rays bursts have pulse durations measured in tens to hundreds of attoseconds (10-18��s).