Related Experiment Video
Updated: Nov 21, 2025
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
10.0K
Transport Efficiency of Continuous-Time Quantum Walks on Graphs
Luca Razzoli1, Matteo G A Paris2,3, Paolo Bordone1,4
1Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università di Modena e Reggio Emilia, I-41125 Modena, Italy.
Entropy (Basel, Switzerland)
|January 13, 2021
Summary
Continuous-time quantum walks model particle transport on graphs. Researchers found graph topology, not just connectivity, dictates transport efficiency, offering benchmarks for quantum transport.
Area of Science:
- Quantum physics
- Graph theory
- Condensed matter physics
Background:
- Continuous-time quantum walk (CTQW) models quantum particle propagation on graphs.
- CTQW is a framework for studying transport phenomena, such as in light-harvesting systems.
- Transport efficiency in CTQW depends on initial states and graph topology.
Purpose of the Study:
- Investigate the influence of graph topology on quantum transport efficiency.
- Analyze how regularity, symmetry, and connectivity affect transport properties.
- Identify subspaces of maximum transport efficiency for different graph structures.
Main Methods:
- Analytical determination of subspaces with maximum transport efficiency.
- Focus on idealized conditions: no disorder or decoherence.
- Modeling with a single trap vertex for loss processes.
Main Results:
- Graph topology significantly impacts quantum transport efficiency.
- Connectivity is generally a poor predictor of transport efficiency.
- Specific correlations between efficiency and connectivity exist for certain graph types, but not universally.
Conclusions:
- Quantum transport efficiency is intricately linked to graph topology beyond simple connectivity.
- The findings provide benchmarks for environment-assisted quantum transport.
- Understanding topological effects is crucial for optimizing quantum transport systems.
Related Concept Videos
01:24Reynolds Transport Theorem
1.6K
The Reynolds transport theorem provides a framework to relate the time rate of change of an extensive property within a system to that in a control volume, which is crucial for analyzing fluid dynamics. Extensive properties, such as mass, velocity, acceleration, temperature, and momentum, can be expressed in terms of the mass of a fluid portion. These properties are called extensive because they depend on the system's size, while intensive properties are their corresponding values per unit...
1.6K
01:10Entropy Change in Reversible Processes
3.0K
In the Carnot engine, which achieves the maximum efficiency between two reservoirs of fixed temperatures, the total change in entropy is zero. The observation can be generalized by considering any reversible cyclic process consisting of many Carnot cycles. Thus, it can be stated that the total entropy change of any ideal reversible cycle is zero.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.
3.0K
01:21Carrier Transport
734
The generation of electrical current in semiconductors is fundamentally driven by two mechanisms: drift and diffusion. These processes are essential for the functionality and performance of semiconductor-based devices.
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
734
02:12Short-distance Transport of Resources
17.0K
Short-distance transport refers to transport that occurs over a distance of just 2-3 cells, crossing the plasma membrane in the process. Small uncharged molecules, such as oxygen, carbon dioxide, and water, can diffuse across the plasma membrane on their own. In contrast, ions and larger molecules require the assistance of transport proteins due to their charge or size. Transport across membranes also occurs within individual cells, playing a variety of essential roles for the plant as a whole.
17.0K
01:27Distribution of Molecular Speeds
4.5K
The motion of molecules in a gas is random in magnitude and direction for individual molecules, but a gas of many molecules has a predictable distribution of molecular speeds. This predictable distribution of molecular speeds is known as the Maxwell-Boltzmann distribution. The distribution of molecular speeds in liquids is comparable to that of gases but not identical and can help to understand the phenomenon of the boiling and vapor pressure of a liquid. Consider that a molecule requires a...
4.5K
01:13Graphing the Wave Function
2.6K
Consider the wave equation for a sinusoidal wave moving in the positive x-direction. The wave equation is a function of both position and time. From the wave equation, two different graphs can be plotted.
2.6K