Seminars

Bose-Einstein condensation with a twist

Speaker(s): 
Cyprian Lewandowski
Dates: 
Monday, January 24, 2022 - 3:30pm

A Pitt/CMU Colloquium

Abstract: Superconductivity is a collective state in which many fermions pair up to give rise to a zero-resistance electron transport regime. The majority of superconductors are well described by a Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity in which a weak momentum space attraction between fermions forms bound Cooper pairs separated in real space. When attraction becomes strong the Cooper pair size shrinks until it effectively forms a diatomic Bose molecule that can, in turn, undergo Bose-Einstein condensation (BEC). A solid-...

Topological plasmonics and out-of-equilibrium plasmonic ferromagnetism

Speaker(s): 
Justin Song
Dates: 
Wednesday, January 19, 2022 - 11:15am

A Pitt/CMU Colloquium

Abstract: Plasmons, the self-sustained collective density modes in metals, form an integral part of the description of interacting electronic systems. Conventionally, plasmon dynamics are often dominated by the density and effective mass of carriers in its host metal. We will discuss how this description falls short in topological materials where the intricate twisting of wavefunctions (i.e. Bloch band quantum geometry) lead to a new class of plasmonic collective modes. These "topological plasmons" possess a wealth of exotic properties...

Exploring New Quantum Materials with Chemistry

Speaker(s): 
Xin Gui
Dates: 
Tuesday, January 18, 2022 - 10:30am

A Pitt Chem Seminar

Abstract: Quantum materials, as an emerging term, include materials with electronic or magnetic properties originating from nontrivial quantum mechanics, such as superconductors, topological materials, quantum spin liquids etc. Such materials are attractive not only due to their exotic quantum physics, but also vast potential applications and corresponding economic benefits. Thus, it is necessary for the communities of solid-state chemistry, condensed matter physics and materials science to explore novel quantum materials and...

Molecular Nano-Architectures for Energy and Electronics

Speaker(s): 
Yu Zhong
Dates: 
Thursday, January 13, 2022 - 10:30am

A Pitt Chem Seminar

Abstract: Since the discovery of conducting polymers, organic materials have promised great applications in energy conversion, electronics, and chemical sensing. Synthetic chemistry has been rapidly advancing the development of organic materials with desired properties and functions. At the core of the research is understanding the structure-property relationships and developing new chemical structures and synthetic methods. In this talk, I will present several design principles of functional organic materials based on the concept of...

Embarking on a Thermal Journey in Low Dimensions with a 21st century thermometer: Graphene Nonlocal Noise

Speaker(s): 
Jonah Waissman
Dates: 
Monday, January 10, 2022 - 3:30pm

A Pitt/CMU Colloquium 

Abstract: Low-dimensional materials, such as 2D monolayers, 1D nanowires, and 0D quantum dots and molecules, are rich with many-body quantum phenomena. The reduced dimensionality, strong interactions, and topological effects lead to new emergent degrees of freedom of fundamental interest and promise for future applications, such as energy-efficient computation and quantum information. Thermal transport, which is sensitive to all energy-carrying degrees of freedom and their interactions, provides a...

Spin physics in graphene nanostructures

Speaker(s): 
Thomas Frederiksen
Dates: 
Friday, December 10, 2021 - 11:30am

A GNR Qubit MURI Seminar

Schedule
11:30a-11:35a General discussion and introductions
11:35a-11:40a Intro to MURI team and concept (Levy)
11:40a-11:50a Blitz talk #1 Davis Welakuh Mbangheku
11:50a-12:00p Blitz talk #2 Erin Sheridan
12:00p-12:50p Thomas Frederiksen talk
12:50p-1:00p Discussion and wrap up

Title: Spin physics in graphene nanostructures

Abstract:

Atomic-scale control over size, shape, and composition of graphenenanostructures has become a reality through on-surface synthesiswhereby...

Local to Meso-scale Order in Electronic Ceramics Characterized by Aberration-Corrected Scanning Transmission Electron Microscopy

Speaker(s): 
Elizabeth Dickey
Dates: 
Friday, December 3, 2021 - 12:15pm

A CMU MSE Seminar

Abstract: The ability to design the composition and microstructure of electronic ceramics for emerging technological applications requires sophisticated characterization techniques that can provide quantitative information about local structure and chemistry. Such structure quantification is particularly important to the fundamental understanding of properties in many important non-linear dielectrics, where chemical heterogeneities associated with dopants or intrinsic lattice defects give rise to local inhomogeneities in charge, strain and...

Structural Inhomogeneity in Oxide Superconductors

Speaker(s): 
Martin Greven
Dates: 
Wednesday, December 8, 2021 - 4:00pm

Abstract: Superconductivity has been a major research topic for more than a century, yet in many important materials this macroscopic quantum phenomenon remains poorly understood. We have uncovered that superconductivity emerges in an unusual, yet remarkably universal manner upon cooling in three well-known families of complex oxides – strontium titanate, strontium ruthenate, and the cuprates – for which the origin of superconductivity is thought to differ [1]. This breakthrough was enabled by nonlinear magnetic response measurements, an innovative experimental approach...

Quantum Advantage in Optical Laser Communications using NISQ-era Quantum Processors

Speaker(s): 
Kaushik P. Seshadreesan
Dates: 
Friday, December 3, 2021 - 11:00am

A PQI Seminar

Abstract: Optical laser communication forms a cornerstone of modern-day data communications. In the quantum-limited regime of lasercom, where the received optical signal power is small, e.g., in deep-space communications, pre-detection quantum domain collective processing of blocks of received signal pulses corresponding to communication codewords can provide enhanced communication capacity. We present a novel quantum receiver design methodology based on a quantum belief propagation algorithm that attains such enhancement. I will discuss the...

Topological Spintronics

Speaker(s): 
Nitin Samarth
Dates: 
Monday, November 22, 2021 - 3:30pm

A Pitt/CMU Physics Colloquium

Abstract: The past decade has witnessed an explosion of activity in exploring the properties of topological quantum materials whose band structure has interesting features arising from the nexus of topology, spin-orbit coupling, and fundamental symmetries. A key characteristic of the band structure in many of these materials is the ‘spin-momentum correlation’ in helical Dirac states. This leads to the notion of ‘topological spintronics’ devices that seek to exploit efficient spin-charge interconversion for low power, non-...

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