Ultra-low temperature magnetic imaging of topological quantum phenomena
Abstract
The objective of this DURIP proposal is to develop an ultra-low temperature magnetic force microscope (ULT-MFM) with high magnetic field for visualizing topological or emergent quantum phenomena in condensed matter physics. The proposed microscope will allow exploration of various intriguing topological quantum phenomena such as dissipationless chiral edge states in quantum anomalous Hall (QAH) systems and devices, unconventional vortices in topological superconductors (TSC), and emergent non-collinear magnetism at oxide interfaces or heterostructures. Topology is pervasive concept in many branches of physics. It underscores many robust phenomena because of topological protection or stability. For example, topology was applied to topological defects such as vortices and dislocations in condense matter systems with spontaneously broken symmetry, which have substantial impact on their functional properties. Recently it is established that topological electronic systems can host a plethora of exotic phenomena such as dissipationless transport without external magnetic field, topological magnetoelectric effects, Majorana zero modes (MZM) for topological quantum computing, etc. The characteristic of these intriguing phenomena is mesoscopic modulation of physical properties or order parameters with non-trivial topology. Thus it is of fundamental interests to detect and visualize these exotic magnetic phenomena with high spatial resolution and high sensitivity. However, most of these topological quantum phenomena emerges at very low temperature, so it is necessary to develop magnetic imaging at ultra-low temperature. Magnetic imaging at extremely low temperature and high magnetic field is technically challenging. Building upon his expertise on cryogenic MFM, the PI will design and construct an ULT-MFM using novel self-sensing cantilevers. The MFM scanner head will be attached to the requested helium 3 refrigerator. The proposed ULT-MFM will enable exciting explorations of many topological and quantum phenomena in quantum materials, e.g., robust QAH effect at elevated temperature, realization of Axion insulators, unconventional vortices and MZM in topological superconductors, and spatially modulated magnetism at oxide interfaces. These exciting projects enabled by the ULT-MFM are in excellent alignment with Army Research OfficeÕs mission on fundamental understandings of topological and correlated phenomena.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 25, 2019
- Source ID
- W911NF1910390
Entities
People
- Weida Wu
Organizations
- Army Contracting Command
- Rutgers University
- United States Army