Digitizing Micromaser Steady States: Entropy, Information Graphs, and Multipartite Correlations in Qubit Registers.

Area of Science:

• Quantum Information Science
• Quantum Optics
• Condensed Matter Physics

Background:

• Characterizing quantum fields requires analyzing their complex correlation structures.
• Digitizing quantum fields onto qubit registers offers a novel approach for analysis.
• Micromasers provide a platform to study driven-dissipative quantum systems.

Purpose of the Study:

• To develop and demonstrate a digitization-based workflow for analyzing quantum field entropy and correlations.
• To investigate the impact of micromaser trapping manifolds on the information graph structure.
• To explore energy and information distribution across qubits in different parameter regimes.

Main Methods:

• Embedding truncated bosonic quantum fields (32 Fock levels) into a five-qubit register.
• Utilizing Gray-code mapping and binary encoding for photon number representation.
• Computing reduced entropies, mutual informations, negativities, and three-tangles.
• Defining and analyzing information graphs based on computed correlation patterns.

Main Results:

• Digitized information graphs clearly reflect the structure of micromaser trapping manifolds.
• Multi-block trapping leads to sparse, banded information graphs with dominant two-qubit links.
• Single manifold trapping or thermal coupling results in more delocalized correlations.
• Entropy and mutual-information profiles offer insights into energy and information distribution.

Conclusions:

• The digitization workflow provides a practical diagnostic for probing the correlation structure of digitized bosonic fields.
• Information graphs serve as structural probes of digitized field states, revealing underlying physics.
• The workflow is transferable to other bosonic fields encoded in small qubit registers.
• This approach aids in understanding driven-dissipative correlation structures in quantum systems.