Detection of spin bias in four-terminal quantum-dot ring

In this work, we show that in a four-quantum-dot ring, via introducing a local Rashba spin-orbit interaction the spin bias in the transverse terminals can be detected by observing the charge currents in the longitudinal probes. It is found that due to the Rashba interaction, the quantum interference in this system becomes spin-dependent and the opposite-spin currents induced by the spin bias can present different magnitudes, so charge currents emerge. Besides, the charge currents rely on both the magnitude and spin polarization direction of the spin bias. It is believed that this method provides an electrical but practical scheme to detect the spin bias (or the spin current).Comment: 6 pages, 5 figure

Cost Shifting the single buyer model with price discrimination' by Lew Evans

This Current Comment was posted by Lew Evans and analyses the current proposal for a single buyer and price discrimination

Free Electricity: What Cost? – What Benefit?' by Lew Evans

This Current Comment by Lew Evans is in response to the article by Susan Edmunds 'Call for free power', New Zealand Herald, 10 February 201

Has Local Loop Unbundling Increased New Zealand's Broadband Uptake?

Current Comment is an occasional series providing economic commentary on topical issues. This second issue looks at local loop unbundling and whether this has increased New Zealand's broadband uptake

Paying When the Trains Run Late

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