DATE:

Friday, September 2, 2022

TIME:

3:30 PM

LOCATION:

GMCS 314

SPEAKER:

Dr. Sanjay Behura, Physics, San Diego State University

ABSTRACT:

Quantum information science for US economic and national security as outlined in the National Quantum Initiative have attracted much research interests in the advanced quantum materials. The key to emerging quantum technologies such as quantum computing and quantum communications is how to produce high quality quantum materials and how to precisely control their quantum states. Two-dimensional (2D) quantum materials and their van der Waals heterostructures with specific orientation and energetics provide precise control of their structure and properties enabling advanced photonic and quantum technologies. Atomically thin 2D quantum materials (quantum flatland) offer a unique platform for the creation of engineered heterostructures with 0D, 1D, 2D and 3D materials with extended range of functionalities. This talk aims to provide the underlying surface physics to build the design-principles for the large-area growth of quantum 2D materials and engineered heterostructures. The first part of the talk is centered on developing large-area, transfer-free hexagonal boron nitride (h-BN) crystals on various dielectric substrates and heterostructures of h-BN with other 2D materials suitable for quantum and photonic circuits. I will discuss equilibrium twist-angle-based Moiré fringes for the direct-growth of graphene on h-BN and the anchoring of plasmonic nanoparticles on sp2 lattice. The second part of the talk is focused on understanding the electrostatic coupling and interfacial dipole formation of 2D layers atop bulk or low-dimensional semiconductors leading to energy-band reorganization and crystal stability, respectively. These mixed-dimensional surface-bound planar or radial heterojunctions create a light-sensitive junction only one-atom below the top surface providing direct access to the photosensitive junction suitable for integrated optoelectronic and photonic circuits.

HOST:

Jose Castillo

VIDEO: