Summary
In this project, we build a solid-state quantum simulator for engineering a specific Hamiltonian. Quantum simulators are purpose-built devices with little to no need for error correction, thereby making this type of hardware less demanding than universal quantum computers. Our platform consists of exciton-polariton condensates in multiple quantum-wells sandwiched in a semiconductor Bragg stack onto which a two-dimensional lattice was imprinted. The lattice imprinting can be achieved, for example, by partial etching of the spacer with the lattice pattern followed by an overgrowth of the upper layers of the Bragg structure.
We are particularly interested in exciton-polariton condensates in a kagome lattice, where we can identify topological properties as a function of particle density. A standard optical technique allows us to quantify wavefunctions of exciton-polaritons. To do this, we construct an interferometer for measurement and use power-dependent photoluminescence to identify quantum phases in the kagome lattice.
Our goal is to advance the measurement of topological parameters and knowledge of condensed matter physics in engineered exciton-polariton simulators. This will serve to elucidate quantum phases in a controlled manner and bring us closer to a quantum simulator capable of delivering meaningful insights into quantum materials and optimization.
Figure 1. (top) A hexagonal lattice of micro-cavities formed in a Bragg stack structure with a spacer (white layer) sandwiching multiple quantum wells (red layers). (bottom) Bandstructures of exciton-polaritons in a two-dimensional kagome lattice. As the pump power changes, exciton-polaritons undergo phase transition to form coherent states: below threshold (a) P/Pth ~ 0.04, near threshold (b) P/Pth ~ 1, and above threshold (c) P/Pth ~ 2, where Pth is the threshold pump power.
Related Content
A Reformulation of Quantum Game Theory
Summary Classical game theory – conducted at the interface between economics and computer science – has found applications in topics ranging from networking and security to online markets. Despite over 20 years of research into connections between game theory and quantum information, we have yet to see any significant implications of quantum information when applied […]
April 1, 2020
Photonic Quantum Processor
Photonic quantum processors based on integrated quantum photonic circuits require entangled photon pairs to perform quantum computations. However, current state-of-the-art technologies utilize probabilistic entangled photon sources with limited pair-extraction efficiencies, negatively affecting the computation speed. This project aims to boost the speed of on-chip quantum operations by using bright, on-demand entangled photon sources with an […]
April 24, 2023
Folk Understanding of Quantum Physics
Summary It is often said that quantum concepts are counterintuitive. However, quantum concepts may not be equally counterintuitive to people from all cultural backgrounds. As cultural psychologists have discovered, culture fundamentally shapes the way people make sense of the world. In particular, the last few decades of research have documented cultural differences in appreciation of […]
March 24, 2021
Scanning Tunneling Microscopy of Quantum Materials, Devices and Molecules
Summary This project advances our ability to characterize and study novel quantum materials, quantum devices, and even individual molecules at the atomic level. By combining Non-Contact Atomic Force Microscopy (NC-AFM), Scanning Tunneling Microscopy (STM) and scanning gate methods, we correlate spatial information with transport properties and can locally manipulate charge, spin and structural states. […]
January 28, 2019