Fall 2019

Cyclotron resonance spectroscopy of symmetry broken states in monolayer graphene

Erik Henriksen
Thursday, November 14, 2019 - 4:30pm

Cyclotron resonance—the resonant absorption of light by charge carriers in a strong magnetic field—is widely used to measure the effective band mass of (semi-)conducting materials. This works because the CR absorption in systems having a parabolic dispersion—a reasonable description of most materials—is unaffected by inter-particle interactions. An intriguing corollary is that, for instance, in high-mobility GaAs heterostructures when the electronic transport shows remarkably complex behavior in the fractional quantum Hall regime, there is still only a single cyclotron resonance peak that...

James McKone highlighted as an emerging investigator in materials chemistry

  • By Jenny Stein
  • 6 November 2019

From the design of improved batteries to the use of solar and wind power for commodity chemical production, the University of Pittsburgh’s James McKone explores ways that chemical engineering can make the world more sustainable. That’s why his most recent work, investigating ways that the chemical industry can use renewable electricity as its energy source, is featured in the Journal of Materials Chemistry A Emerging Investigators special issue.

The themed issue highlights the rising stars of materials chemistry research, from nanoparticle inks to next-generation solar cells. The featured investigators are early in their careers and were recommended by other experts in the field.  “We’re glad to have James on our faculty and know this honor is well-deserved,” says Steven Little, PhD, chair of the Department of Chemical and Petroleum Engineering at the Swanson School. “It confirms what we already know: that his lab’s work has the potential to influence the direction of future discoveries in energy production, energy storage and beyond.” 

Discovering Perovskites

Feliciano Giustino
Friday, November 22, 2019 - 11:30am

In this talk I will illustrate how quantum-mechanical modeling of materials at the atomic scale plays an important role in solar energy research, and how it can be used to design and realize entirely new materials. After an introduction to solar photovoltaics, I will discuss the emergence of perovskite solar cells during the past few years, and explain why this family of materials has attracted so much interest in the scientific community. One of the outstanding challenges in perovskite research is to find new lead-free materials with optoelectronic properties comparable to lead-based...

Machine Learning for Materials Discovery

Maxwell Hutchison
Friday, November 8, 2019 - 11:30am

Machine learning and artificial intelligence applications in science and engineering have received rapidly increasing hype over the last several  years, with Citrine on the front lines of adoption of ML and AI in materials development. In this talk, I will discuss opportunities, open challenges, and recent work in materials informatics drawn from experiences on a wide range of commercial and noncommercial projects, including:

  • data    reuse    with    transfer    learning,
  • design    of    experiments    with    active    learning,
  • domain    knowledge    
  • ...

Nanorod Heterostructures: from Colloidal Solutions to Light Emitting/Harvesting Devices

Moonsub Shim
Wednesday, October 30, 2019 - 12:00pm

The ability to efficiently separate, recombine, and direct charge carriers is central to a wide range of applications, including electronics, photovoltaics, displays and solid-state lighting. Engineering band structure and heterointerfaces with atomic precision is an obvious route to achieving such capabilities. To do so through widely-accessible and cost-effective means is not. But such a means would allow rapid advances in these critical application areas. The evolution of colloidal semiconductor nanocrystals from single-composition, “spherical” particles to complex heterostructures of...

Tevis Jacobs: Infectiously inspiring in the classroom

  • By Jenny Stein
  • 15 October 2019

In his classroom, engineering faculty member Tevis Jacobs is one animated presenter.

He speaks rapidly and enthusiastically while adding diagrams to clear overlays on two screens of slides projected onto the white board.  The course is “Mechanical Behavior of Materials,” which examines how things bend and break, down to their atomic structures. Today’s class encompasses the concepts of “work hardening,” “twinning,” and nickel-based super alloys (“You guys know that is my favorite topic,” Jacobs says). 

Jacobs joined the faculty of the Swanson School of Engineering in fall 2015, teaching this undergraduate class and another on experimental techniques, and offering one on tribology — the study of friction, wear and lubrication of sliding surfaces — to graduate students.

“I’ve always wanted to understand how the world works,” Jacobs says. “Mechanical engineering and materials science: what I like about them is that they are all around us. We are constantly interacting with objects, seeing how they perform. I like the idea of making them better in the future … but the current goal is (studying) ‘Why did this thing happen in this way?’ “What I love,” he adds, “especially in the classes I’m teaching now: we can answer that.”

Quantum sensing and quantum nanophotonics at ORNL

Benjamin Lawrie
Thursday, November 21, 2019 - 4:00pm

Two-mode squeezed light sources exhibiting continuous variable entanglement allow us to reduce the noise floor in optically transduced sensors below the standard quantum limit, enabling greater signal to noise ratios than are possible in the best possible classical sensors.  I will present some of our recent results demonstrating quantum enhanced sensitivity for applications ranging from magnetometry to plasmonic sensing to atomic force microscopy. I will also discuss some of our recent research efforts exploring quantum nanophotonics with plasmonic nanostructures and single photon...

Quantum Information Processing with Spins in Diamond

Gurudev Dutt
Wednesday, October 16, 2019 - 12:00pm

A key feature of quantum physics is the existence of superpositions of single and many-particle quantum states, usually referred to as quantum coherence and entanglement respectively.  Famously, these aspects of quantum theory were also characterized by Einstein as "spooky" and caused him to reject many of its predictions. However, these principles are by now so well established that they have actually become tools in the growing field of quantum information science and technology to realize new paradigms for secure communication, enhanced computation, and precision sensing. 


To Advance Additive Manufacturing / 3D Printing with Quantum Perspectives

Xiayun Zhao
Thursday, December 12, 2019 - 4:00pm

Additive manufacturing (AM), known as 3D Printing, has given rise to powerful capabilities for converting 3D digital models into physical objects. The valuable features of AM include the ability to build parts with tailored properties for custom applications, the high efficiency of material utilization, and the unprecedented flexibility for fabricating complex or intricated structures that cannot be made by traditional manufacturing processes. 

AM has been over 30 years old since its inception, and yet the technology is still a frontier with unexplored potentials partly due to the...