相关论文: Shot noise in a diffusive F-N-F spin valve
We measure the frequency spectra of random spin fluctuations, or "spin noise", in ensembles of (In,Ga)As/GaAs quantum dots (QDs) at low temperatures. We employ a spin noise spectrometer based on a sensitive optical Faraday rotation…
The intrinsic fluctuations of electron spins in semiconductors and atomic vapors generate a small, randomly-varying "spin noise" that can be detected by sensitive optical methods such as Faraday rotation. Recent studies have demonstrated…
We present our first experimental determination of the magnetic noise of a superspinglass made of < 1 pico-liter frozen ferrofluid. The measurements were performed with a local magnetic field sensor based on Hall microprobes operated with…
We have derived a general formula describing current noise in multimode ballistic channels connecting source and drain electrodes with Fermi electron gas. In particular (at $eV\gg k_{B}T$), the expression describes the nonequilibrium…
In the conventional spin noise spectroscopy, the probe laser light monitors fluctuations of the spin orientation of a paramagnet revealed as fluctuations of its gyrotropy, i.e., circular birefringence. For spins larger than 1/2, there…
We report on a novel spin-charge fluctuation in the all-in-all-out pyrochlore magnet Cd$_2$Os$_2$O$_7$, where the spin fluctuation is driven by the conduction of thermally excited electrons/holes and associated fluctuation of Os valence.…
We report shot noise measurements for a quantum dot formed in an InAs nanowire suspended between superconducting electrodes. We find a clear alternation for the shot noise value in the Coulomb blockade regime between even and odd electron…
Spin polarized current may transfer angular momentum to a ferromagnet, resulting in a spin-torque phenomenon. At the same time the shot noise, associated with the current, leads to a non-equilibrium stochastic force acting on the…
We investigate current fluctuations in non-degenerate semiconductors, on length scales intermediate between the elastic and inelastic mean free paths. We present an exact solution of the non-linear kinetic equations in the regime of…
We present theoretical study of shot noise in single wall metallic carbon nanotubes weakly coupled to either nonmagnetic or ferromagnetic leads. Using the real-time diagrammatic technique, we calculate the current, Fano factor and tunnel…
Current fluctuations can provide additional insight into quantum transport in mesoscopic systems. The present work is carried out for the fluctuation properties of transport through a pair of coupled quantum dots which are connected with…
Theoretical and experimental work concerned with dynamic fluctuations has developed into a very active and fascinating subfield of mesoscopic physics. We present a review of this development focusing on shot noise in small electric…
The spin-transfer in biased disordered ferromagnet (F) - normal metal (N) systems is calculated by the diffusion equation. For F1-N2-F2 and N1-F1-N2-F2-N3 spin valves, the effect of spin-flip processes in the normal metal and ferromagnet…
We present fluctuation relations that connect spin-polarized current and noise in mesoscopic conductors. In linear response, these relations are equivalent to the fluctuation-dissipation theorem that relates equilibrium current--current…
We report an exact solution for the noise spectrum of spin-current without charge-current in a spin field effect transistor (SFET). For the SFET with two leads, it is found that both auto- and cross-correlation functions are needed to…
The nature of charge carriers in strange metals has become a topic of intense current investigation. Recent shot noise measurements in the quantum critical heavy fermion metal YbRh$_2$Si$_2$ revealed a suppression of the Fano factor that…
We have investigated shot noise and conductance of multi-terminal graphene nanoribbon devices at temperatures down to 50 mK. Away from the charge neutrality point, we find a Fano factor $F \approx 0.4$, nearly independent of the charge…
We consider fluctuation relations between the transport coefficients of a spintronic system where magnetic interactions play a crucial role. We investigate a prototypical spintronic device (a spin-diode) which consists of an interacting…
We report a comprehensive study of stochastic electron spin fluctuations -- spin noise -- in lightly doped ($n$-type) bulk GaAs, which are measured using sensitive optical magnetometry based on off-resonant Faraday rotation. Frequency…
Surface electric (charge) noise influences spin defects due to fluctuation of the surface charge density and also the electrostatic potential at the crystal surface. Surprisingly, the two-point correlation function of both the charged…