Past Events

Low-dimensional perovskites for light-emitting applications: What do we need and how to make it?

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Jawaher Almutlaq, Postdoctoral Fellow
Research Laboratory of Electronics

The first part of this talk covers the controversy regarding the origin of emission in zero-dimensional perovskites (0D), Cs₄PbBr₆ and Cs₄PbI₆, through a comparative analysis between 0D and three-dimensional (3D) perovskites.

Then, Almutlaq will address the shortcoming of lead-based perovskites in terms of toxicity and stability, motivated by the high demand for sustainable materials with analogous electrical and structural properties. Finally, Almutlaq will share the recent work on CsMnBr₃ NCs, which reveals an intense red PL peak, a high PLQY with a remarkable excitation spectrum and surprisingly short lifetime. This work paves the way for finding sustainable materials for the next generation of light-emitting applications.

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Waveguide quantum electrodynamics with artificial superconducting giant atoms

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Bharath Kannan, PhD Candidate
Electrical Engineering & Computer Science

Models of light-matter interactions typically invoke the dipole approximation, within which atoms are treated as point-like objects when compared to the wavelength of the electromagnetic modes with which they interact. However, when the ratio between the size of the atom and the mode wavelength is increased, the dipole approximation no longer holds and the atom is referred to as a "giant atom".

Thus far, experimental studies with solid-state devices in the giant-atom regime have been limited to superconducting qubits that couple to short-wavelength surface acoustic waves, only probing the properties of the atom at a single frequency. Here, Kannan and others employ an alternative architecture that realizes a giant atom by coupling small atoms to a waveguide at multiple, but well separated, discrete locations.

Their realization of giant atoms enables tunable atom-waveguide couplings with large on-off ratios and a coupling spectrum that can be engineered by device design. They also demonstrate decoherence-free interactions between multiple giant atoms that are mediated by the quasi-continuous spectrum of modes in the waveguide—an effect that is not possible to achieve with small atoms. These features allow qubits in this architecture to switch between protected and emissive configurations in situ while retaining qubit-qubit interactions, opening new possibilities for high-fidelity quantum simulations and non-classical itinerant photon generation.

We continue to improve the nanousers event module through testing of the registration customization and automated emails. Soon we will use this feature for tool trainings and events.

Cavity–enhanced microwave readout of a diamond sensor

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Erik Eisenach, PhD Candidate
Electrical Engineering & Computer Science
MIT Lincoln Laboratory

In this talk, Eisenach will discuss how he and fellow researchers leverage strong coupling between an ensemble of solid-state spins and a dielectric microwave cavity for high-fidelity, room-temperature readout of nitrogen-vacancy centers. Using this strong collective interaction, they probe the spin ensemble’s microwave transition directly, overcoming the optical photon shot noise limitations of conventional fluorescence readout. Furthermore, they apply this technique to magnetometry, and show magnetic sensitivity approaching the Johnson–Nyquist noise limit of the system.

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Small molecule assemblies with a bulletproof design: The aramid amphiphile

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Ty Christoff-Tempesta, PhD Candidate
Materials Science & Engineering

Small molecule self-assembly offers a powerful bottom-up approach to producing nanostructures with high surface areas, tunable surfaces, and defined internal order. Historically, the dynamic nature of these systems has limited their use to specific cases, especially biomedical applications, in solvated environments.

In the talk, Christoff-Tempesta will present a self-assembling small molecule platform, the aramid amphiphile (AA), that overcomes these dynamic limitations.

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During this training Dr. Ted Limpoco, Application Scientist with Oxford-Asylum Research will go over the basics of the Jupiter AFM operation.

Prior AFM experience is required.

Zoom details will be shared with the registered users.

Practical fiber batteries for wearables based on thermally drawn Zn-MnO2

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ENS Maximilian Ulbert
Research Fellow
MIT Lincoln Laboratory

The concept of the Internet-of-Things has inspired growth in the field of wearable technology, from aesthetically-pleasing color changing fabrics to practical heart rate monitors, all interwoven into any variety of clothes (ie. shirts, pants, hats, blankets, bags, etc.). For a continuously operating wearable system, an energy storage vessel is needed: a battery.

This work seeks to address both assembly and safety issues by developing an easily manufacturable fiber battery by means of a thermal draw tower using a safer Zn-ion chemistry (Zn/MnO2) with a gel polymer electrolyte (GPE). As the GPE offers a high ionic conductivity, mechanical properties compatible with thermal draw towers and provides a physical separator between cathode and anode, the performance of lab scale prototypes and a drawn-fiber prototype will be discussed.

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Enabling atomic resolution Cryogenic Electron Microscopy

Presented by Jeff Lengyel, Principal Scientist

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This presentation will discuss recent technological advancements in various aspects of Cryo-EM. These recent developments will not only enhance throughput, but also the resolution achieved with single particle analysis and cryo-electron tomography.

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Integrated photonics and electronics for chip-scale quantum control of trapped ions

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Jules Stuart, Research Assistant
MIT Lincoln Laboratory
Physics PhD candidate, 2021

Trapped atomic ions are promising candidates for quantum information processing and quantum sensing. Current state-of-the-art trapped-ion systems require many lasers and electronics to achieve precise timing and control over quantum states.  Usually, electronic signals are sent into vacuum chambers via wire feedthroughs, and laser light is focused down to a trapped ion’s location with external lenses mounted outside of viewports on the chamber. These requirements lead to dense and complex setups that may be prone to drift and limit the amount of control that can be achieved.

In this presentation, Stuart will report on recent progress toward integrating control technology into the substrate of the ion trap itself. By using a planar trap design, which is compatible with lithographic fabrication, other well-developed processes may be implemented in order to enhance the function of the ion trap. In one experiment, researchers demonstrate an ion trap with integrated, CMOS-based high-voltage sources, which can be used to control the motional frequency and position of a trapped ion. In another demonstration, they use photonic waveguides and diffractive grating couplers to route light around a chip and focus it onto ions trapped above the surface.

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Tuesday, February 16, 2021
11 a.m. – 11:45 a.m. EST

James McRae, Graduate student
Mechanical Engineering (MechE)
MIT Lincoln Laboratory, Advanced Materials & Microsystems

Electronic microsystems are foundational to today’s computational, sensing, communication, and information processing capabilities, therefore impacting industries such as microelectronics, aerospace, healthcare, and many more. Cell phones are an example of what is possible when a variety of systems can be tightly integrated into a highly portable and capable system. However, as we aim to improve our ability to interact and operate (e.g., sense, communicate, record, compute, move, etc.) in extreme environments (such as outer space or the human body), new methods and materials must be developed to manufacture such integrated systems that will endure post-processing, environmental, and operational challenges.

Typical organic-based packaging materials (e.g., polymer adhesives, coatings, and molding materials) often suffer from outgassing and leaching that can lead to system contamination, as well as coefficient of thermal expansion (CTE) mismatches that can lead to warpage and breakage with fluctuations in system temperature during operation. This work demonstrates an alternative, by using a silicate-based inorganic glass composite as an electronics packaging material for stability in extreme environments. Combining liquid alkali sodium silicate (water glass) and nanoparticle fillers, composites can be synthesized and cured at low temperatures into chemically, mechanically, and thermally (up to 400 oC) stable structures using high throughput processing methods such as spin and spray coating. Further, this material can be processed into thick layers (10s to 100s of microns), fill high aspect ratio gaps (13:1), withstand common microfabrication processes, and have its CTE tailored to match various substrates.

Attendees can join and participate in the series via Zoom. Meeting ID#: 860 986 455.

>>See the upcoming schedule and watch past talks.