Tuesday, January 28th, 2020

Time	Event
12:00a	Testing the waters In 2010, the U.S. Army Corps of Engineers began restoring the Broad Meadows salt marsh in Quincy, Massachusetts. The marsh, which had grown over with invasive reeds and needed to be dredged, abutted the Broad Meadows Middle School, and its three-year transformation fascinated one inquisitive student. “I was always super curious about what sorts of things were going on there,” says Rachel Shen, who was in eighth grade when they finally finished the project. She’d spend hours watching birds in the marsh, and catching minnows by the beach. In her bedroom at home, she kept an eye on four aquariums furnished with anubias, hornwort, guppy grass, amazon swords, and “too many snails.” Now, living in a dorm as a sophomore at MIT, she’s had to scale back to a single one-gallon tank. But as a Course 7 (Biology) major minoring in environmental and sustainability studies, she gets an even closer look at the natural world, seeing what most of us can’t: the impurities in our water, the matrices of plant cells, and the invisible processes that cycle nutrients in the oceans. Shen’s love for nature has always been coupled with scientific inquiry. Growing up, she took part in Splash and Spark workshops for grade schoolers, taught by MIT students. “From a young age, I was always that kid catching bugs,” she says. In her junior year of high school, she landed the perfect summer internship through Boston University’s GROW program: studying ant brains at BU’s Traniello lab. Within a colony, ants with different morphological traits perform different jobs as workers, guards, and drones. To see how the brains of these castes might be wired differently, Shen dosed the ants with serotonin and dopamine and looked for differences in the ways the neurotransmitters altered the ants’ social behavior. This experience in the Traniello lab later connected Shen to her first campus job working for MITx Biology, which develops online courses and educational resources for students with Department of Biology faculty. Darcy Gordon, one of the administrators for GROW and a postdoc at the Traniello Lab, joined MITx Biology as a digital learning fellow just as Shen was beginning her first year. MITx was looking for students to beta-test their biochemistry course, and Gordon encouraged Shen to apply. “I’d never taken a biochem course before, but I had enough background to pick it up,” says Shen, who is always willing to try something new. She went through the entire course, giving feedback on lesson clarity and writing practice problems. Using what she learned on the job, she’s now the biochem leader on a student project with the It’s On Us Data Sciences club (formerly Project ORCA) to develop a live map of water contamination by rigging autonomous boats with pollution sensors. Environmental restoration has always been important to her, but it was on her trip to the Navajo Nation with her first-year advisory group, Terrascope, that Shen saw the effects of water scarcity and contamination firsthand. She and her peers devised filtration and collection methods to bring to the community, but she found the most valuable part of the project to be “working with the people, and coming up with solutions that incorporated their local culture and local politics.” Through the Undergraduate Research Opportunities Program (UROP), Shen has put her problem-solving skills to work in the lab. Last summer, she interned at Draper and the Velásquez-García Group in MIT’s Microsystems Technologies Laboratories. Through experiments, she observed how plant cells can be coaxed with hormones to reinforce their cell walls with lignin and cellulose, becoming “woody” — insights that can be used in the development of biomaterials. For her next UROP, she sought out a lab where she could work alongside a larger team, and was drawn to the people in the lab of Sallie “Penny” Chisholm in MIT’s departments of Biology and Civil and Environmental Engineering, who study the marine cyanobacterium Prochlorococcus. “I really feel like I could learn a lot from them,” Shen says. “They’re great at explaining things.” Prochlorococcus is one of the most abundant photosynthesizers in the ocean. Cyanobacteria are mixotrophs, which means they get their energy from the sun through photosynthesis, but can also take up nutrients like carbon and nitrogen from their environment. One source of carbon and nitrogen is found in chitin, the insoluble biopolymer that crustaceans and other marine organisms use to build their shells and exoskeletons. Billions of tons of chitin are produced in the oceans every year, and nearly all of it is recycled back into carbon, nitrogen, and minerals by marine bacteria, allowing it to be used again. Shen is investigating whether Prochlorococcus also recycles chitin, like its close relative Synechococcus that secretes enzymes which can break down the polymer. In the lab’s grow room, she tends to test tubes that glow green with cyanobacteria. She’ll introduce chitin to half of the cultures to see if specific genes in Prochlorococcus are expressed that might be implicated in chitin degradation, and identify those genes with RNA sequencing. Shen says working with Prochlorococcus is exciting because it’s a case study in which the smallest cellular processes of a species can have huge effects in its ecosystem. Cracking the chitin cycle would have implications for humans, too. Biochemists have been trying to turn chitin into a biodegradable alternative to plastic. “One thing I want to get out of my science education is learning the basic science,” she says, “but it’s really important to me that it has direct applications.” Something else Shen has realized at MIT is that, whatever she ends up doing with her degree, she wants her research to involve fieldwork that takes her out into nature — maybe even back to the marsh, to restore shorelines and waterways. As she puts it, “something that’s directly relevant to people.” But she’s keeping her options open. “Currently I'm just trying to explore pretty much everything.” (Comment on this)
3:20p	A trapped-ion pair may help scale up quantum computers Of the many divergent approaches to building a practical quantum computer, one of the most promising paths leads toward ion traps. In these traps, single ions are held still and serve as the basic units of data, or qubits, of the computer. With the help of lasers, these qubits interact with each other to perform logic operations.     Lab experiments with small numbers of trapped ions work well, but a lot of work remains in figuring out the basic parts of a scalable ion-trap quantum computer. What kind of ions should be used? What technologies will be able to control, manipulate, and read out the quantum information stored in those ions? Toward answering these questions, MIT Lincoln Laboratory researchers have turned to a promising pair: ions of calcium (Ca) and strontium (Sr). In a paper published in npj Quantum Information, the team describes using these ions to perform quantum logic operations and finds them to be favorable for multiple quantum computing architectures. Among their advantages, these ions can be manipulated by using visible and infrared light, as opposed to ultraviolet, which is needed by many types of ions being used in experiments. Unlike for ultraviolet light, technology that would be able to deliver visible and infrared light to a large array of trapped ions already exists. “What kind of quantum information processing architecture is feasible for trapped ions? If it turns out it will be much more difficult to use a certain ion species, it would be important to know early on, before you head far down that path,” says John Chiaverini, senior staff in the Quantum Information and Integrated Nanosystems Group. “We believe we won't have to invent a whole new engineered system, and not solve a whole new group of problems, using these ion species.” Cold and calculating To trap ions, scientists start with a steel vacuum chamber, housing electrodes on a chip that is chilled to nearly 450 degrees below zero Fahrenheit. Ca and Sr atoms stream into the chamber. Multiple lasers knock electrons from the atoms, turning the Ca and Sr atoms into ions. The electrodes generate electric fields that catch the ions and hold them 50 micrometers above the surface of the chip. Other lasers cool the ions, maintaining them in the trap.  Then, the ions are brought together to form a Ca+/Sr+ crystal. Each type of ion plays a unique role in this partnership. The Sr ion houses the qubit for computation. To solve a problem, a quantum computer wants to know the energy level, or quantum state, of an ion's outermost electron. The electron could be in its lowest energy level or ground state (denoted), some higher energy level or excited state (denoted), or both states at once. This strange ability to be in multiple states simultaneously is called superposition, and it is what gives quantum computers the power to try out many possible solutions to a problem at once.  But superposition is hard to maintain. Once a qubit is observed — for example, by using laser light to see what energy level its electron is in — it collapses into either a 1 or 0. To make a practical quantum computer, scientists need to devise ways of measuring the states of only a subset of the computer's qubits while not disturbing the entire system. This need brings us back to the role of the Ca ion — the helper qubit. With a similar mass to the Sr ion, it takes away extra energy from the Sr ion to keep it cool and help it maintain its quantum properties. Laser pulses then nudge the two ions into entanglement, forming a gate through which the Sr ion can transfer its quantum information to the Ca ion. “When two qubits are entangled, their states are dependent on each other. They are so-called 'spookily correlated,'” Chiaverini said. This correlation means that reading out the state of one qubit tells you the state of the other. To read out this state, the scientists interrogate the Ca ion with a laser at a wavelength that only the Ca ion's electron will interact with, leaving the Sr ion unaffected. If the electron is in the ground state it will emit photons, which are collected by detectors. The ion will remain dark if in an excited metastable state.  “What's nice about using this helper ion for reading out is that we can use wavelengths that don't impact the computational ions around it; the quantum information stays healthy. So, the helper ion does dual duty; it removes thermal energy from the Sr ion and has low crosstalk when I want to read out just that one qubit,” says Colin Bruzewicz, who built the system and led the experimentation. The fidelity of the Ca+/Sr+ entanglement in their experiment was 94 percent. Fidelity is the probability that the gate between the two qubits produced the quantum state it was expected to — that the entanglement worked. This system's fidelity is high enough to demonstrate the basic quantum logic functionality, but not yet high enough for a fully error-corrected quantum computer. The team also entangled ions in different configurations, such as the two ions on the ends of a Sr+/Ca+/Sr+ string, with similar fidelity. A wavelength match Currently, the ion-trap setup is large and choreographs the use of 12 different-colored lasers. These lasers stream through windows in the cryogenic chamber and are aimed to hit the ions. A practical quantum computer — one that can solve problems better than a classical computer — will need an array of thousands or even millions of ions. In that scenario, it would be practically impossible to hit precisely the right ions while not disturbing the quantum states in neighboring ions. Lincoln Laboratory researchers have been working for the past several years on a way deliver the lasers up through “gratings” in the chip the ions hover above. This integrated-photonic chip both simplifies the setup and ensures that the right laser hits the intended target. Last year, the team achieved the first-ever successful demonstration of a low-loss, integrated photonics platform with light delivery ranging from the visible to the infrared spectrum. Conveniently, the wavelengths required for cooling Ca and Sr ions, entangling them, and reading them out all fall within this same spectrum. This overlap simplifies the system's laser requirements, unlike other pairings of ions that each require widely different wavelengths. “These ions lend themselves to being used with integrated photonics. They're a wavelength match. It makes engineering sense to use them,” Bruzewicz says. In addition, many types of trapped ions that quantum scientists are exploring need ultraviolet light for excitation. But ultraviolet light can be difficult to work with. Waveguides and other photonic devices that carry the light to the ions tend to lose some of the light on the way. Delivering ultraviolet light to large-scale trapped-ion systems would require a lot more power, or the engineering of new materials that experience less loss.  “It's much simpler working with this light than the ultraviolet, especially when you start to put a lot of these ions together. But that's the challenge — no one actually knows what kind of architecture will enable quantum computation that’s helpful. The jury is still out,” Chiaverini reflects. “In this instance, we are thinking about what might be most advantageous to scaling up a system. These ions are very amenable to that.” (Comment on this)
4:00p	Surveying the quality of life at MIT The MIT Council on Family and Work today released a new Quality of Life Survey for faculty, staff, and students at MIT. Results from the voluntary and anonymous survey, which can be taken starting today, will inform initiatives to improve the work-life experience for the MIT campus community and Lincoln Laboratory. Faculty and staff were surveyed on similar issues in 2012 and 2016, students in 2013 and 2017. Beginning this year, the entire MIT community is being surveyed at the same time. The council’s co-chairs, Amy Glasmeier, a professor in the Department of Urban Studies and Planning, and Ken Goldsmith, assistant dean for finance and administration in the School of Architecture and Planning, view the 2020 survey as an opportunity to gather data from the community that will inform senior leadership about how to make MIT a supportive and inclusive environment where everyone can excel. Email invitations, sent today to the MIT community, include a link to the web-based survey, which covers a range of topics — from satisfaction and workload concerns to the intersection of work and personal/family life. The Council on Family and Work is committed to maximizing the response rate for all sectors of the community to ensure the results are as representative as possible. The 2020 survey is more streamlined than earlier versions and, while still comprehensive, should take less than 25 minutes to complete. Many of the survey questions have been asked over time, which allows the Council on Family and Work to understand what aspects of MIT’s culture have changed or stayed the same. The survey is being administered by MIT Institutional Research (IR) in the Office of the Provost. Results will be presented in a way that ensures the confidentiality of individual responses. For the purposes of analysis, IR may combine other data with responses to the survey. The Quality of Life survey is a primary source of information about the experiences of members of the MIT community, such as the importance of flexibility in the workplace, perceptions on the availability of resources to complete a person’s job, having friends at work, and feeling respected by others. By understanding the distribution of these perspectives within our community, MIT will have more information about the types of support services it needs to provide. From responses to recommendations Results of the survey are used in a variety of ways. In the spirit of transparency, overall results will be posted on the IR public website in the form of an interactive Tableau Report. Additional analysis will be done in conjunction with the Council, including comparisons with prior years. Summary results will be available to individual units to inform their leaders on issues specific to their areas, provided there are sufficient responses to ensure confidentiality for individual respondents. Later in the year, the Council on Family and Work will publish a comprehensive report. Other reports may focus on specific subjects — such as workplace flexibility, as one example — or subgroups at MIT, such as gender, race/ethnicity, international origin, and sexual orientation. The intention is to identify areas in which MIT is doing a good job as well as areas for improvement. One of the highest priorities of the council is the protection of individual responses. The more candid the response, the more useful the data. But while the council is committed to transparency of the results, it is equally committed to the confidentiality of the individual response. Role of the MIT Council on Family and Work The Council on Family and Work was established in 1992 by then-MIT president Charles Vest. The council is a presidentially appointed committee overseen by the executive vice president and treasurer. MIT’s first major committee to focus on these issues was the Ad Hoc Committee on Family and Work, formed in 1989, which recommended the establishment of the council. At the beginning, the council focused primarily on issues related to women and children (e.g., maternity leave, childcare). In the last 10 years the focus has broadened to incorporate long-term pressing needs and concerns of the whole community. Culture, climate, and engagement are major themes of the survey. The council works closely with the MIT Work-Life Center and the Employee Benefits Oversight Committee. Topics under discussion include flexible work arrangements and improving the tuition assistance program. There have also been enhancements to the employee assistance program, which helps faculty and staff deal with a suite of life-course challenges, from elderly parents to legal issues to difficulty managing finances. Glasmeier notes that this program, now in its third year, is used far more at MIT than at other universities. A change in co-chair James Bales, associate director at the Edgerton Center, recently stepped down as co-chair of the MIT Council on Family and Work. He served on the council for 10 years and played a central role in the last two Quality of Life Surveys. He helped with both the front-end work of getting the questions right and the back-end work of getting the reports done. The council recently welcomed its new co-chair, Ken Goldsmith, who believes that significant strides get made when people get involved. He and Glasmeier encourage MIT faculty, staff, and students to take the 2020 Quality of Life survey to help make MIT an inviting, inclusive, progressive and well-liked place to study and work. To access your survey or learn more, visit ir.mit.edu/qol. (Comment on this)

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