THEORY OF NON-LINEAR 2D SPECTROSCOPY FOR TOPOLOGICAL QUANTUM MATTER
Abstract
We will theoretically develop a new general diagnosis method for topological quantum states, which can be experimentally implemented in the lab. The topological quantum states include quantum Hall liquids and spin liquids, which exhibit the non-local fractional particles. Because of the fractionalized particles, information can be stored non-locally in space and processed without decoherence. This makes the topological quantum states an ideal platform for quantum computation. However, how these states can be unambiguously identified in experiments is still unclear. Solid state physics of the last fifty years is founded upon the framework of the linear response theory and associated experimental measurement such as spin susceptibility. The linear response made great success in diagnosing usual phases of matter such as magnetism. However, it cannot be applied to detect fractional excitations of topological quantum states. Hence, one needs to go beyond the standard realm of the linear response theory. Indeed, it has been previously suggested in a few simple models that certain non-linear responses can detect the fractional excitation and thus the non-local entanglement. However, the systematic understanding of the non-linear responses for generic topological quantum states is absent. Motivated from this, we will systematically investigate the non-linear 2D spectroscopy of various topological quantum states. We believe that our proposal will provide a guiding principle for characterizing topological quantum states in the lab and this will in turn greatly help the realization of quantum computers based on topological quantum states. Our proposal will also broaden the realm of modern condensed matter physics beyond “linear response theory”.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 11, 2021
- Source ID
- FA23862014029
Entities
People
- Gil Young Cho
Organizations
- Air Force Office of Scientific Research
- Pohang University of Science and Technology
- United States Air Force