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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
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Rotational-permutational dual-pairing and long-lived spin order
1School of Chemistry, University of Southampton, University Road SO17 1BJ, United Kingdom.
The Journal of Chemical Physics
|February 10, 2020
Summary
Long-lived spin order in quantum systems arises from symmetries. This study introduces a framework using Schur-Weyl duality to analyze these symmetries, refining bounds on long-lived spin populations and coherences.
Area of Science:
- Quantum Dynamics
- Quantum Information Science
- Condensed Matter Physics
Background:
- Quantum systems interacting with thermal environments exhibit both coherent and incoherent dynamics.
- These dynamics drive quantum systems back to thermal equilibrium after perturbation, involving population reorganization and coherence decay.
- Individual populations and coherences can have distinct relaxation times, with specific configurations showing exceptionally long relaxation times, termed long-lived spin order.
Purpose of the Study:
- To establish a theoretical framework for studying rotational and permutational dual-symmetries in the context of long-lived spin order.
- To leverage the Schur-Weyl duality theorem for analyzing these symmetries in nuclear spin systems.
- To derive refined bounds on the number of long-lived spin populations and coherences in systems with rotational-permutational dual-symmetries.
Main Methods:
- Application of the Schur-Weyl duality theorem to describe dual-symmetries.
- Development of a theoretical formalism to analyze the impact of these symmetries on spin dynamics.
- Derivation of refined bounds for long-lived spin order characteristics.
Main Results:
- A theoretical framework is presented for the study of rotational and permutational dual-symmetries.
- The framework provides a method to identify and analyze spin configurations with exceptionally long relaxation times (long-lived spin order).
- Refined bounds are derived for the number of long-lived spin populations and coherences in relevant quantum systems.
Conclusions:
- Long-lived spin order is a direct consequence of system symmetries, particularly rotational and permutational symmetries in nuclear spin systems.
- The developed theoretical framework, based on Schur-Weyl duality, offers a powerful tool for understanding these symmetries.
- The derived bounds provide quantitative insights into the persistence of order in quantum systems interacting with thermal environments.
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