A5057431369- Electronic and Structural Properties of Oxides
- Semiconductor materials and devices
- Magnetic and transport properties of perovskites and related materials
- Ferroelectric and Negative Capacitance Devices
- Advanced Condensed Matter Physics
- Ferroelectric and Piezoelectric Materials
- 2D Materials and Applications
- Physics of Superconductivity and Magnetism
- Analytical Chemistry and Sensors
- Electron and X-Ray Spectroscopy Techniques
- Advanced X-ray and CT Imaging
- Advanced Memory and Neural Computing
- Graphene and Nanomaterials Applications
- Supramolecular Self-Assembly in Materials
- Advanced Photocatalysis Techniques
- Dendrimers and Hyperbranched Polymers
- Advanced Sensor and Energy Harvesting Materials
- Acoustic Wave Resonator Technologies
- Molecular Junctions and Nanostructures
- Graphene research and applications
- Plasmonic and Surface Plasmon Research
- Advanced Materials Characterization Techniques
- Zeolite Catalysis and Synthesis
- Magneto-Optical Properties and Applications
- MXene and MAX Phase Materials
University of Pittsburgh
2020-2025
Pittsburgh Quantum Institute
2020-2024
The origin and function of chirality in DNA, proteins, other building blocks life represent a central question biology. Observations spin polarization magnetization associated with electron transport through chiral molecules, known collectively as the induced selectivity (CISS) effect, suggest that improves transfer by inhibiting backscattering. Meanwhile, role coherence within nanowires is believed to be important but challenging investigate experimentally. Using reconfigurable nanoscale...
The discovery of two-dimensional superconductivity in <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:msub><a:mrow><a:mi>LaAlO</a:mi></a:mrow><a:mn>3</a:mn></a:msub><a:mo stretchy="false">/</a:mo><a:msub><a:mrow><a:mi>KTaO</a:mi></a:mrow><a:mn>3</a:mn></a:msub></a:mrow></a:math> (111) and (110) interfaces has raised significant interest this system. In paper, we report the first successful fabrication a direct current superconducting quantum interference...
KTaO 3 heterostructures have recently attracted attention as model systems to study the interplay of quantum paraelectricity, spin-orbit coupling, and superconductivity. However, high low vapor pressures potassium tantalum present processing challenges creating heterostructure interfaces clean enough reveal intrinsic properties. Here, we report superconducting based on high-quality epitaxial (111) thin films using an adsorption-controlled hybrid PLD overcome pressure mismatch. Electrical...
Freestanding membranes of electronically reconfigurable complex oxide heterostructure are demonstrated.
Recent reports of superconductivity at KTaO3 (KTO) (110) and (111) interfaces have sparked intense interest due to the relatively high critical temperature as well other properties that distinguish this system from more extensively studied SrTiO3 (STO)-based heterostructures. Here, we report reconfigurable creation conducting structures intrinsically insulating LaAlO3/KTO(110) interfaces. Devices are created using two distinct methods previously developed for STO-based heterostructures: (1)...
Pristine, undoped graphene has a constant absorption of 2.3 % across the visible to near-infrared (VIS-NIR) region electromagnetic spectrum. Under certain conditions, such as nanostructuring and intense gating, can interact more robustly with VIS-NIR light exhibit large nonlinear optical response. Here, we explore properties graphene/LaAlO$_3$/SrTiO$_3$ nanostructures, where nanojunctions formed at LaAlO$_3$/SrTiO$_3$ interface enable (~10$^8$ V/m) electric fields be applied over scale ~10...
We describe a method to control the insulator–metal transition at LaAlO3/SrTiO3 interface using ultra-low-voltage electron beam lithography. Compared previous reports that utilize conductive atomic force microscope (c-AFM) lithography, this approach can provide comparable resolution (∼10 nm) write speeds (10 mm/s) are up 10 000× faster than c-AFM. The writing technique is nondestructive, and state reversible via prolonged exposure air. Transport properties of representative devices measured...
Heterostructures composed of different layered materials provide novel opportunities to investigate the electronic correlations between them. Here we frictional drag graphene and ${\mathrm{LaAlO}}_{3}/{\mathrm{SrTiO}}_{3}$ (LAO/STO) heterostructures. The LAO/STO layer underneath is rendered conductive using atomic force microscope (c-AFM) lithography, creating a two-layer system in which LAO serves as an ultrathin ($<$2 nm) insulating barrier. By sourcing current both STO layer, Coulomb...
The LaAlO$_3$/SrTiO$_3$ interface hosts a plethora of gate-tunable electronic phases. Gating interfaces are usually assumed to occur electrostatically. However, increasing evidence suggests that non-local interactions can influence and, in some cases, dominate the coupling between applied gate voltages and properties. Here, we sketch quasi-1D ballistic electron waveguides at as probe understand how tunability varies function spatial separation. Gate measurements reveal scaling law be odds...
Abstract The LaAlO 3 /SrTiO interface hosts a plethora of gate‐tunable electronic phases. Gating interfaces is usually assumed to occur electrostatically. However, increasing evidence suggests that non‐local interactions can influence and, in some cases, dominate the coupling between applied gate voltages and properties. Here, quasi‐1D ballistic electron waveguides are sketched at as probe understand how tunability varies function spatial separation. Gate measurements reveal scaling law be...
The ability to create superlattices in van der Waals (vdW) heterostructures via moir\'e interference heralded a new era the science and technology of two-dimensional materials. Through precise control twist angle, flat bands strongly correlated phases have been engineered. twisting vdW layers is some sense bottom-up approach--a single parameter can dial wide range periodic structures. Here, we describe top-down approach engineering nanoscale potentials using buried programmable ferroelectric...
A wide family of two dimensional (2D) systems, including stripe-phase superconductors, sliding Luttinger liquids, and anisotropic 2D materials, can be modeled by an array coupled one-dimensional (1D) electron channels or nanowire arrays. Here we report experiments in arrays conducting nanowires with gate field tunable interwire coupling, that are programmed at the LaAlO$_3$/SrTiO$_3$ interface. We find a magnetically-tuned metal-to-insulator transition which transverse resistance increases...
We demonstrate an approach to creating nanoscale potentials in van der Waals layers integrated with a buried programmable ferroelectric layer. Using ultra-low-voltage electron beam lithography (ULV-EBL), we can program the polarization Al
Strontium titanate (STO), apart from being a ubiquitous substrate for complex-oxide heterostructures, possesses multitude of strongly coupled electronic and mechanical properties. Surface acoustic wave (SAW) generation detection offers insight into electromechanical couplings that are sensitive to quantum paraelectricity other structural phase transitions. Propagating SAWs can interact with STO-based nanostructures, in particular ${\mathrm{LaAlO}}_{3}/{\mathrm{SrTiO}}_{3}$ (LAO/STO). Here,...
KTaO3 has recently attracted attention as a model system to study the interplay of quantum paraelectricity, spin-orbit coupling, and superconductivity. However, high low vapor pressures potassium tantalum present processing challenges creating interfaces clean enough reveal intrinsic properties. Here, we report superconducting heterostructures based on electronic-grade epitaxial (111) thin films. Electrical structural characterizations that two-dimensional electron gas at heterointerface...
The discovery of two-dimensional superconductivity in LaAlO3/KTaO3 (111) and (110) interfaces has raised significant interest this system. In manuscript we report the first successful fabrication a superconducting quantum interference device (DC-SQUID) KTO key elements, weak links, are created by conductive atomic force microscope (c-AFM) lithography which can reversibly control conductivity at LAO/KTO(110) interface with nanoscale resolution. periodic modulation SQUID critical current,...