Demonstrating W-type Entanglement of Dicke-States in Resonant Cavity Quantum Electrodynamics

Abstract

Nonlinearity and entanglement are two important properties by which physical systems can be identified as non-classical. We study the dynamics of the resonant interaction of up to N=3 two-level systems and a single mode of the electromagnetic field sharing a single excitation dynamically. We observe coherent vacuum Rabi oscillations and their nonlinear speed up by tracking the populations of all qubits and the resonator in time. We use quantum state tomography to show explicitly that the dynamics generates maximally entangled states of the W class in a time limited only by the collective interaction rate. We use an entanglement witness and the threetangle to characterize the state whose fidelity F=78% is limited in our experiments by crosstalk arising during the simultaneous qubit manipulations which is absent in a sequential approach with F=91%.

References in corpus (8)

• Charge insensitive qubit design derived from the Cooper pair box
• Entanglement detection
• Strong atom-field coupling for Bose-Einstein condensates in an optical cavity on a chip
• Strong Coupling of a Spin Ensemble to a Superconducting Resonator
• Cavity QED with a Bose-Einstein condensate
• Dressed Collective Qubit States and the Tavis-Cummings Model in Circuit QED
• Analytic control methods for high fidelity unitary operations in a weakly nonlinear oscillator
• Two-Qubit State Tomography using a Joint Dispersive Read-Out

Cited by in corpus (10)

• Observation of Dicke Superradiance for Two Artificial Atoms in a Cavity with High Decay Rate
• Observation of the photon-blockade breakdown phase transition
• Exploring the quantum critical behaviour in a driven Tavis-Cummings circuit
• Simulating weak localization using superconducting quantum circuits
• Fermionic Models with Superconducting Circuits
• Quantum Batteries: A Materials Science Perspective
• Critical light-matter entanglement at cavity mediated phase transition
• On-chip generation and collectively coherent control of the superposition of the whole family of Dicke states
• Mirror and cavity formations by chains of collectively radiating atoms
• Coherent Control with User-Defined Passage