We report an experimental demonstration of a heterodyne polarization rotation measurement with a noise floor 4.8 dB below the optical shot noise by use of classically phase-locked quantum twin beams emitted above threshold by an ultrastable type II Na:KTP cw optical parametric oscillator. We believe that this is the largest noise reduction achieved to date in optical phase-difference measurements.

The current shot-noise of an electron beam is proportional to its average current and the frequency bandwidth. This is a consequence of the Poisson distribution statistics of particles emitted at random from any source. Here we demonstrate noise suppression below the shot-noise limit in optical frequencies for relativistic electron beams. This process is made possible by collective Coulomb inte...

We review recent studies of the shot noise of spin-polarized charge currents and pure spin currents in multiterminal semiconductor nanostructures, while focusing on the effects brought by intrinsic Rashba spin-orbit (SO) coupling and/or extrinsic SO scattering off impurities. By generalizing the scattering theory of quantum shot noise to include the full spin-density matrix of electrons injecte...

In this article, the quantum correlation measurement technique as a method of power noise monitoring is investigated. Its principal idea correlating two photodetector signals introduced and contrasted to conventional approach, which uses only single photodetector. We discuss how scheme can be used obtain information below shot detected beam also electronic dark individual photodetectors, both n...

This article studies the scaling limit of a class of shot-noise fields defined on an independently marked stationary Poisson point process and with a power law response function. Under appropriate conditions, it is shown that the shot-noise field can be scaled suitably to have a non degenerate α-stable limit, as the intensity of the underlying point process goes to infinity. More precisely, fin...

We report the noise characteristics of quantum point contacts between 100 Hz and 100 kHz at 4.2 K. The noise consists of a 111 component on top of a white background. The 1I/noise increases as the contact width decreases and shows peaks between the quantized resistance plateaus. The white noise background increases with current but is much lower than the fuB shot noise level, suggesting that sh...

Molecular spintroinic device based on a single-molecule magnet is one of the ultimate goals of semiconductor nanofabrication technologies. It is thus necessary to understand the electron transport properties of a single-molecule magnet junction. Here we study the negative differential conductance and super-Poissonian shot noise properties of electron transport through a single-molecule magnet w...

The advent of stable, highly squeezed states of light has generated great interest in the gravitational wave community as a means for improving the quantum-noise-limited performance of advanced interferometric detectors. To confidently measure these squeezed states, it is first necessary to measure the shot-noise across the frequency band of interest. Technical noise, such as non-stationary eve...

The Lyman-alpha forest has become an important tool for measuring the mass power spectrum at high redshifts (z = 2−4). A crucial intermediate step is the measurement of the transmission power spectrum. We present new methods to minimize the systematic and random errors for such a measurement, and discuss their implications for observing strategies. Sources of systematic errors explored include ...