Advancing the frontiers of science often requires the creation of new probes to uncover the
underlying microscopic mechanisms giving rise to exotic macroscopic phenomena, such as high-
temperature superconductivity. Can quantum entangled probes uncover the inherent
entanglement of the target matter? We have recently [1-3] developed an entangled neutron
beam where individual neutrons can be entangled in spin, trajectory, and energy. To
demonstrate entanglement in these beams we crafted neutron interferometric measurements
of contextuality inequalities whose violation provided an indication of the breakdown of
Einstein's local realism. In turn, the tunable entanglement (spin-echo) length of the neutron
beam from nanometers to microns and energy differences from peV to neV opens a pathway to
a future era of entangled neutron scattering in matter. What kind of information can be
extracted with this novel entangled probe? A recent general quantum many-body entangled-
probe scattering theory [4] provides a framework to respond to this question. Interestingly, by
carefully tuning the probe's entanglement and inherent coherence properties, one can directly
access the intrinsic entanglement of the target material. This theoretical framework supports
the view that our entangled beam can be used as a multipurpose scientific tool. We are
currently [5] pursuing several ideas and developing new spin-textured entangled beams with
OAM for future experiments in candidate quantum spin liquids, unconventional
superconductors, and chiral quantum materials.

[1] J. Shen et. al., Nature Commun. 11, 930 (2020).
[2] S. Lu et. al., Phys. Rev. A 101, 042318 (2020).
[3] S. J. Kuhn et. al., Phys. Rev. Research 3, 023227 (2021).
[4] A. A. Md. Irfan, P. Blackstone, R. Pynn, and G. Ortiz, New J. Phys. 23, 083022 (2021).
[5] Q. Le Thien, S. McKay, R. Pynn, and G. Ortiz, arXiv:2207.12419.

What physics does one hope to learn by looking closely at exotic quantum states of matter, esoteric to begin with, but even more so on curved surfaces?! In this talk first I will remind the audience why quantum hall states serve as paradigmatic topological quantum states of matter, highlighting their signature property: the quantization of Hall conductance, which is independent of sample-specific details to the extent that it is used for precise measurements of fundamental constants. Tracing the topological origin of this remarkable property, I will motivate by analogy the interplay between the geometry of these states and their response to “gravitational” perturbations, i.e., deformations to the real space manifold they are embedded in — on a cone, for example! This then naturally leads to a discussion of what, if any, universal signatures characterize this response. Finally, some reflections on the broader implications of these excursions, and connections to other branches of physics, including classical soft matter systems.

Short bio:
Dr. Biswas received his PhD from Harvard University, working with Prof. Subir Sachdev on experimentally relevant exotic quantum states of matter.  Prof. Bert Halperin served as mentor. While at Harvard Rudro held several fellowships including the James Mills Pierce Fellowship Award, the Purcell Fellowship and the Harvard Center for Energy and Environment Fellowship. Following postdoctoral research as an Institute of Condensed Matter Theory Fellow at UIUC, Rudro became an Assistant Professor of Physics at Purdue University, where he is currently.

Cuprate high-temperature superconductors feature rich phase diagrams due to the presence of various competing degrees of freedom, inevitable disorder and high anisotropy. In cuprates, the value of the upper critical magnetic field (H_c2) and the role of charge and spin orders have long been under debate. In order to reveal the nature of the quantum phases (T -> 0) and transitions between them, in a varied magnetic field, as well as to investigate the precise interplay of charge order, disorder, and high temperature superconductivity, we perform transport measurements on (1) underdoped Bi₂Sr_0.16La_0.84CuO_6+δ, which exhibits short-range charge order, (2) overdoped Bi_2.1Sr_1.9CuO_6+δ and (3) highly overdoped Bi₂Sr₂O_6+δ, where charge order has not been observed yet. Measurements of linear transport, non-linear transport and Hall effect were performed in magnetic fields (H) up to 45 T and temperatures (T) down to 17 mK.

Plastic semiconductors incorporated into transistors have shown enormous potential for low-cost, flexible, printable electronics and bioelectronics. In my talk, I will discuss their history, operating mechanisms, and potential applications. I will highlight key challenges to these applications, and discuss some of the approaches I've taken to overcome them. I will show how these simple solutions can work towards the broad realization of organic transistors.

Carbon Based Nano Electromechanics: Physics and Applications

Sang Wook Lee

Department of Physics, Ewha Womans University, Seoul, 03760, Korea

E-mail: leesw@ewha.ac.kr

In this presentation, physical properties and possible applications of carbon based nano electro-mechanical devices

(NEMS) will be introduced. Our research started from carbon nanotube based nano electro-mechanical relay

structure and expanded to graphene-based xylophone and drum like devices. Micro contact transfer method is

applied to realize the suspended nano structures with various electrodes under the nano materials. Recently

developed pick-up and transfer technique made us possible to fabricate various stacking and suspended nano

structures. After introducing some interesting physical properties, such as basic mechanical switching and

resonance behaviour and light emission of suspended graphene structures, possible application of carbon based

nano electro-mechanical devices will be suggested. Graphene based ultra-sensitive mass detector will be suggested

for one of the promising applications of our devices and our recent research project on single protein sequencing

using graphene-based mass detector will be introduced at the end of presentation.

Although in recent years researchers have committed significant efforts investigating properties and potential functionalities of metal oxides, commercially available oxide-based devices still
remain quite limited. Reasons for this include high material costs, sophisticated/non-scalable growth techniques, and insufficient enhancements over current industry standards. Our aim is
to narrow the divide that separates fundamental research and functional applications by developing efficient synthesis methods for strategic materials that will be highly impactful on
society. In particular we have identified tungsten oxide owing to its large abundance, optical bandgap, and versatile physical properties as an ideal candidate for photocatalytic hydrogen
production which has potential to provide a positive paradigm shift in society’s demand for fossil fuel generated energy, especially in developing portions of the world. Here I will discuss two
parallel approaches towards synthesizing tungsten oxide nanostructures that are cost effective, time efficient, and scalable along with their morphology, crystallinity, electronic properties, and
potential for utilization in functional devices.

Dr. Ankur Das

Postdoctoral Research Associate

Weizmann Institute of Science

Rehovot, Israel

Title: Detection of 5/2 phases

Abstract: The phases of the \nu=5/2 state have been shown to be very elusive but one of the most interesting ones as it is proposed to contain Majorana modes with non-abelian statistics. There is more than one candidate for the non-abelian state and among that three are the most promising ones namely pfaffian, anti-pfaffian, and particle-hole symmetric pfaffian. Quite a few experiments later the issue has not been settled. Previous efforts proposed methods to distinguish the candidates including the proposals where the order can be determined by measuring both thermal conductances and shot noise on the same device [Park et al. PRL 125, 157702 (2020)] or by only measuring the unequilibrated electrical conductance [Yutushui et al. PRL 128, 016401 (2022)]. To avoid some of the experimental challenges and limitations of the proposals including the above-mentioned ones we propose a new device made out of interfaces of the \nu=5/2 state and Abelian states. We propose to measure electrical shot noise to resolve among these states.

Professor John Davis

Associate Professor

University of Alberta

Department of Physics

Title:  Superfluid Helium Electromechanics

Abstract: Liquid helium posses many properties that make it an attractive medium for studies of mechanical systems in the quantum regime, such as low mechanical and dielectric losses.  The flip side of this is to imagine using optomechanics or electromechanics to revisit the novel physics of superfluid helium, including bosonic helium-4 and fermionic helium-3.  In particular, when spatially restricted in one dimension, helium superfluids are expected to demonstrate quasi-two dimensional behavior with qualitatively different physics than in three dimensions.  By using nanofabrication techniques to both confine the helium and provide an electromechanical detection scheme, we are beginning the journey of studying such two-dimensional superfluids.

Dr. Allen Scheie

Postdoctoral Research Associate

Oak Ridge National Laboratory

Neutron Scattering Division

Title: Witnessing entanglement in quantum magnets using neutron scattering

Abstract: In this talk I show how information about solid state quantum entanglement can be extracted from magnetic neutron scattering using model-independent techniques. Using the 1D spin chain KCuF3, we examine three entanglement witnesses applicable to neutron scattering: one tangle, two tangle, and Quantum Fisher Information (QFI). We find that QFI is the most experimentally robust, giving good agreement between theory and experiment over all measured temperatures, and witnessing multipartite entanglement up to 75 K. We then apply the entanglement witnesses to the 2D triangular lattice KYbSe2, showing the presence of appreciable entanglement in the low temperature phase. We then use diffuse scattering fits, heat capacity comparisons, and nonlinear spin wave fits to demonstrate that KYbSe2 is proximate to a quantum spin liquid. We thus provide a rigorous route to studying and understanding highly entangled quantum phases.

Professor Jun Hee Lee

School of Energy and Chemical Engineering

Ulsan National Institute of Science and Technology

South Korea

Title: Ultimate-density atomic semiconductor via flat phonon bands

Abstract: Dispersion-less flat energy bands in momentum space generate localized states and are known to cause unconventional phenomena such as graphene superconductivity in electrons and individual spin flips in magnons. However flat bands in phonon were not discovered yet. For the first time, we discovered flat bands in phonon exist surprisingly in a ferroelectric HfO₂ and produce a localized motion of atoms as if their chemical bond temporarily disappears by an external voltage. With the vanishing bond, each atom can be freely displaced by the voltage for the information storage. Our discovery of the atom control directly in a solid will lead us to the design of ultimate-density memory semiconductors reaching up to ~100 TB [1]. Our theory is directly applicable to the Si-compatible HfO₂ so can be materialized in all electronic devices [2]. Just as Einstein’s theory of relativity (E=mc²) enabled us to make bombs out of atoms not out of materials, with our “Atomic Semiconductor” we will open the era of designing memories on an atomic scale rather than a materials scale and carrying a data center in the palm of your hand.

[1] “Scale-free ferroelectricity driven by flat phonon bands in HfO₂”, H.-J. Lee et al., Science 369, 1343 (2020).

[2] “A key piece of the ferroelectric hafnia”, B. Noheda et al., Science 369, 1300 (2020).