Related papers: Ratchet effect in dc SQUIDs
Cold atoms in optical lattices have emerged as an ideal system to investigate the ratchet effect, as demonstrated by several recent experiments. In this work we analyze theoretically two aspects of ac driven transport in cold atoms…
The radio frequency (rf) Superconducting QUantum Interference Device (SQUID) is a highly nonlinear oscillator exhibiting rich dynamical behavior. It has been studied for many years and it has found numerous applications in magnetic field…
We investigate the quantum ratchet effect under the influence of weak dissipation which we treat within a Floquet-Markov master equation approach. A ratchet current emerges when all relevant symmetries are violated. Using time-reversal…
We investigate the Josephson diode effect in an asymmetric SQUID consisting of a sinusoidal Josephson junction formed by a Bi$_2$Te$_2$Se flake and a superconducting Nb nanobridge with a linear and multivalued current-phase relation (CPR).…
A superconducting quantum interference device with differential output or "DSQUID" was proposed earlier for operation in the presence of large common-mode signals. The DSQUID is the differential connection of two identical SQUIDs. Here we…
We investigate the transport properties of a new class of ratchets. The device is constructed by applying an ac voltage to the metallic single electron tunneling transistor, and a net transport current is induced by the time-dependent…
Traditionally the charge ratchet effect is considered as a consequence of the extrinsic spatial asymmetry engineered by external asymmetric periodic potentials. Here we demonstrate that electrically and magnetically driven dissipative…
In this work, the ratchet dynamics of Brownian particles driven by an external sinusoidal (harmonic) force is investigated. The gating ratchet effect is observed when another harmonic is used to modulate the spatially symmetric potential in…
We experimentally investigate the phenomenon of a quantum ratchet created by exposing a Bose-Einstein Condensate to short pulses of a potential which is periodic in both space and time. Such a ratchet is manifested by a directed current of…
We simulate vortices in superconductors interacting with two-dimensional arrays of triangular traps. We find that, upon application of an ac drive, a net dc flow can occur which shows current reversals with increasing ac drive amplitude for…
We have measured and propose a model for switching rates in hysteretic DC-SQUID in the regime where phase diffusion processes start to occur. We show that the switching rates in this regime are smaller than the rates given by Kramers'…
Risken's matrix continued fraction method is used to solve the Fokker-Planck equation to calculate particle current in an inertial symmetric (sinusoidal) periodic potential under the action of a constant force. The particle moves in a…
A thorough analysis of the dynamics in a deterministic optical rocking ratchet (introduced in A. V. Arzola et al., Phys. Rev. Lett. 106, 168104 (2011)) and a comparison with experimental results are presented. The studied system consists of…
The current-voltage curves and magnetic dependence of the critical current of asymmetric superconducting loops are measured. It was found that sign and value of the asymmetry of the current-voltage curves changes with value of magnetic…
A dc voltage induced by an external ac current is observed in system of asymmetric mesoscopic superconducting loops. The value and sign of this dc voltage, like the one of the persistent current, depend in a periodical way on a magnetic…
We study theoretically the spatial distribution of the polarizations in the array of resonant electromagnetic dipole emitters coupled to a one-dimensional waveguide. The ratchet effect manifests itself in the spatial asymmetry of the…
We explore the non-linear dynamics of two parallel periodically patterned metal surfaces that are coupled by the zero-point fluctuations of the electromagnetic field between them. The resulting Casimir force generates for asymmetric…
We report measurements of coherence times of an rf SQUID qubit using pulsed microwaves and rapid flux pulses. The modified rf SQUID, described by an double-well potential, has independent, in situ, controls for the tilt and barrier height…
We report on the observation of the magnetic quantum ratchet effect in graphene with a lateral dual-grating top gate (DGG) superlattice. We show that the THz ratchet current exhibits sign-alternating magneto-oscillations due to the…
We study two capacitively coupled double quantum dots focusing on the regime in which one double dot is strongly biased, while no voltage is applied to the other. Then the latter experiences an effective driving force which induces a…