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Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
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A Magic Ratio Rule for Beginners: A Chemist's Guide to Quantum Interference in Molecules
Colin J Lambert1, Shi-Xia Liu2
1Quantum Technology Centre, Physics Department, Lancaster University, Lancaster, LA1 4YB, UK.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|November 10, 2017
Summary
Chemists can now design molecular electronic devices by controlling quantum interference (QI) effects. A new magic ratio rule (MRR) predicts conductance in single-molecule junctions, guiding the creation of functional materials.
Area of Science:
- Molecular electronics
- Quantum chemistry
- Materials science
Background:
- Room temperature quantum interference (QI) in single-molecule junctions is a growing area of interest.
- Tailor-made molecular electronic devices require precise control over QI effects.
Purpose of the Study:
- To present chemical design principles for exploiting quantum interference (QI) in molecular-scale devices.
- To introduce a new conceptual framework for controlling QI through chemical modification.
Main Methods:
- Discussion of QI from a chemical perspective.
- Introduction of the magic ratio rule (MRR) for predicting charge transport.
- Analysis of connectivity-driven charge transport in polycyclic aromatic hydrocarbons (PAHs).
Main Results:
- The MRR provides a minimal description of connectivity-driven charge transport.
- MRR predicts conductance ratios determined by QI within PAH cores.
- QI manifestations are linked to weak coupling, locality, connectivity, mid-gap transport, and phase coherence.
Conclusions:
- Chemical modification offers a route to control QI effects in single molecules.
- The MRR serves as a practical tool for chemists designing molecular electronic devices.
- Understanding QI is crucial for materials discovery in molecular electronics.
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