Quantum pumping as a dynamical probe of the superfluid response of a onedimensional (1D) quantum fluid is discussed. It is shown that a spatially periodic potential, oscillating adiabatically in time with frequency !0, acts as a quantum pump inducing a continuous momentum current from broken spatiotemporal symmetries of the driven potential. The momentum current generated by the pump is strongly affected by the interactions. It has a power-law dependence on the frequency and the temperature with the exponent determined by the interaction. It depends on the phase difference between two umklapp terms of the drive, providing indication for the effect of quantum phase slips on the decay of superflow. Application of the results in understanding the superfluid properties of helium confined in nanometer-size pores or of laser-cooled atoms is briefly discussed.
A dynamical probe of superfluidity in one-dimension: The adiabatic quantum pump
CITRO, Roberta
2012-01-01
Abstract
Quantum pumping as a dynamical probe of the superfluid response of a onedimensional (1D) quantum fluid is discussed. It is shown that a spatially periodic potential, oscillating adiabatically in time with frequency !0, acts as a quantum pump inducing a continuous momentum current from broken spatiotemporal symmetries of the driven potential. The momentum current generated by the pump is strongly affected by the interactions. It has a power-law dependence on the frequency and the temperature with the exponent determined by the interaction. It depends on the phase difference between two umklapp terms of the drive, providing indication for the effect of quantum phase slips on the decay of superflow. Application of the results in understanding the superfluid properties of helium confined in nanometer-size pores or of laser-cooled atoms is briefly discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
