Transfers and Development: Easy Come, Easy Go?

Contrary to the popular notion that money that is easily earned, is also easily spent, economic theory holds that income is fungible. Drawing on the concept of mental accounting, this study theoretically explores when such a link between spending behaviour and the effort dispensed in obtaining income is plausible. Empirically, it is found that the marginal propensity to consume from unearned income is about three times larger than that from earned income, based on household panel data from rural China, with the difference more pronounced when unearned income is transitory and smaller than earned income. The policy implications are real

Radiation-induced magnetoresistance oscillation in a two-dimensional electron gas in Faraday geometry

Microwave-radiation induced giant magnetoresistance oscillations recently discovered in high-mobility two-dimensional electron systems in a magnetic field, are analyzed theoretically. Multiphoton-assisted impurity scatterings are shown to be the primary origin of the oscillation. Based on a model which considers the interaction of electrons with the electromagnetic fields in Faraday geometry, we are able not only to reproduce the correct period, phase and the negative resistivity of the main oscillation, but also to obtain secondary peaks and additional maxima and minima in the resistivity curve, some of which were already observed in the experiments.Comment: 4 pages, 1 figure, revised version to be published in Phys. Rev. Let

Pumped spin-current and shot noise spectra in a single quantum dot

We exploit the pumped spin-current and current noise spectra under equilibrium condition in a single quantum dot connected to two normal leads, as an electrical scheme for detection of the electron spin resonance (ESR) and decoherence. We propose spin-resolved quantum rate equations with correlation functions in Laplace-space for the analytical derivation of the zero-frequency atuo- and cross-shot noise spectra of charge- and spin-current. Our results show that in the strong Coulomb blockade regime, ESR-induced spin flip generates a finite spin-current and the quantum partition noises in the absence of net charge transport. Moreover, spin shot noise is closely related to the magnetic Rabi frequency and decoherence and would be a sensitive tool to measure them.Comment: 4 pages, 3 figures, to be published in Phys. Rev. Lette

Disorder effects on the spin-Hall current in a diffusive Rashba two-dimensional heavy-hole system

We investigate the spin-Hall effect in a two-dimensional heavy-hole system with Rashba spin-orbit coupling using a nonequilibrium Green's function approach. Both the short- and long-range disorder scatterings are considered in the self-consistent Born approximation. We find that, in the case of long-range collisions, the disorder-mediated process leads to an enhancement of the spin-Hall current at high heavy-hole density, whereas for short-range scatterings it gives a vanishing contribution. This result suggests that the recently observed spin-Hall effect in experiment is a result of the sum of the intrinsic and disorder-mediated contributions. We have also calculated the temperature dependence of spin-Hall conductivity, which reveals a decrease with increasing the temperature.Comment: 5 pages, 2 figures, Typos in the values of hole density correcte