相关论文: Current fluctuations in a single tunnel junction
We study current fluctuations in tunnel junctions driven by a voltage source. The voltage is applied to the tunneling element via an impedance providing an electromagnetic environment of the junction. We use circuit theory to relate the…
We examine current fluctuations in tunnel junctions driven by a superposition of a constant and a sinusoidal voltage source. In standard setups the external voltage is applied to the tunneling element via an impedance providing an…
In this article we present simple approaches to the calculation of P(i) (the probability distribution of current fluctuations) in a tunnel junction, and to the effect of the environment on noise measurements in terms of the modification of…
Fluctuations of the current through a tunnel junction are measured using a Josephson junction. The current noise adds to the bias current of the Josephson junction and affects its switching out of the supercurrent branch. The experiment is…
The conductance fluctuations of a metallic wire which is interrupted by a small tunnel junction has been explored experimentally. In this system, the bias voltage V, which drops almost completely inside the tunnel barrier, is used to probe…
We study the current noise spectra of a tunnel junction of a metal with strong pairing phase fluctuation and a superconductor. It is shown that there is a characteristic peak in the noise spectrum at the intrinsic Josephson frequency…
The statistics of electron transport in a quantum conductor is affected by fluctuations of its voltage bias. Here we show experimentally how a third order correlation in the electromagnetic field arises from the noise of a tunnel junction…
New experiments that measure the low-frequency shot-noise spectrum at local tunneling contacts on mesoscopic structures are proposed. The current fluctuation spectrum at a single tunneling tip is determined by local partial densities of…
Frequency dependent current noise in ferromagnetic double junctions with Coulomb blockade is studied theoretically in the limit of sequential tunneling. Two different relaxation processes are found in the correlations between spin polarized…
We present the first measurements of the third moment of the voltage fluctuations in a conductor. This technique can provide new and complementary information on the electronic transport in conducting systems. The measurement was performed…
We analyze the dynamics of a nanomechanical oscillator coupled to an electrical tunnel junction with an arbitrary voltage applied to the junction and arbitrary temperature of electrons in leads. We obtain the explicit expressions for the…
Quantum mechanics can strongly influence the noise properties of mesoscopic devices. To probe this effect we have measured the current fluctuations at high-frequency (5-90 GHz) using a superconductor-insulator-superconductor tunnel junction…
Current and its noise in a ferromagnetic double tunnel barrier device with a small spacer particle were studied in the framework of the sequential tunneling approach. Analytical formulae were derived for electron tunneling through the…
We present a simple microscopic model to show how fluctuating two--level systems in the Josephson junction tunnel barrier of thickness $L$ can modify the potential energy of the barrier and produce critical current noise spectra. We find…
We report measurements of the correlation between intensities of noise at different frequencies on a tunnel junction under ac excitation, which corresponds to two-mode intensity correlations in optics. We observe positive correlation,…
We have investigated the mechanism at the origin of the infra-red radiation emitted by a biased tunnel junction by detecting photons at frequencies $\nu<eV/h$. To address this regime, the bias voltage $V$ exceeds one volt and the potential…
Current fluctuations generated by tunnel junctions are known to be non-Gaussian. However, this property is lost when fluctuations are measured at high frequency and limited bandwidth. We show that the quadratures of the electric field…
Employing the non-linear $\sigma$-model we analyze current fluctuations in coherent composite conductors which contain a diffusive element in-between two tunnel barriers. For such systems we explicitly evaluate the frequency-dependent third…
Intrinsic noise is known to be ubiquitous in Josephson junctions. We investigate a voltage biased superconducting tunnel junction including a very small number of pinholes - transport channels possessing a transmission coefficient close to…
We report the first experimental data of the third moment of current fluctuations in a tunnel junction. We show that both in the classical and quantum regimes (low or high frequency as compared to voltage), it is given by $S_{I^3}=e^2I$. We…