A three-terminal Josephson junction biased at opposite voltages can sustain a phase-sensitive dccurrent carrying three-body static phase coherence, known as the "quartet current". We calculate the zero-frequency current noise cross-correlations and answer the question of whether this current is noisy (like a normal current in response to a voltage drop) or noiseless (like an equilibrium supercurrent in response to a phase drop). A quantum dot with a level at energy 0 is connected to three superconductors Sa, S b and Sc with gap ∆, biased at Va = V , V b = −V and Vc = 0, and with intermediate contact transparencies. At zero temperature, nonlocal quartets (in the sense of four-fermion correlations) are noiseless at subgap voltage in the nonresonant dot regime 0/∆ 1, which is demonstrated with a semi-analytical perturbative expansion of the cross-correlations. Noise reveals the absence of granularity of the superflow splitting from Sc towards (Sa, S b ) in the nonresonant dot regime, in spite of finite voltage. In the resonant dot regime 0/∆ < ∼ 1, crosscorrelations measured in the (Va, V b ) plane should reveal an "anomaly" in the vicinity of the quartet line Va + V b = 0, related to an additional contribution to the noise, manifesting the phase sensitivity of cross-correlations under the appearance of a three-body phase variable. Phase-dependent effective Fano factors Fϕ are introduced, defined as the ratio between the amplitudes of phase modulations of the noise and the currents. At low bias, the Fano factors Fϕ are of order unity in the resonant dot regime 0/∆ < ∼ 1, and they are vanishingly small in the nonresonant dot regime 0/∆ 1.
We investigate the effect of breaking the parity of a photonic crystal waveguide designed to have odd and even modes intersecting inside the photonic bandgap. The complete study on the wavefields properties of the resulting bonding modes uncovers that the transverse spin and orbital parts of the angular momentum couple in the very slow-light regime by the means of their local currents. This leads to a sub-bandgap opening between bands characterized by distinct organizations of this spinorbit coupling at the nano-scale.
The Random Telegraph Noise (RTN) in an advanced Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) is considered to be triggered by just one electron or one hole, and its importance is recognised upon the aggressive scaling. However, the detailed nature of the charge trap remains to be investigated due to the difficulty to find out the exact device, which shows the RTN feature over statistical variations. Here, we show the RTN can be observed from virtually all devices at low temperatures, and provide a methodology to enable a systematic way to identify the bias conditions to observe the RTN. We found that the RTN was observed at the verge of the Coulomb blockade in the stability diagram of a parasitic Single-Hole-Transistor (SHT), and we have successfully identified the locations of the charge traps by measuring the bias dependence of the RTN.
In a line-defect waveguide of a planer photonic crystal (PhC), we found a new rotational state of polarized light, which exhibits "polarization rotation" on the PhC plane, when a phase mismatch m was added to the air-hole alignment of the waveguide, where mode splitting was simultaneously observed in the dispersion curve. To account for the polarization rotation together with the mode splitting, we propose a two-state model that is constructed from Schrödinger equation obtained from the equation for electromagnetic waves. The proposed two-state model gives an explanation on the relation between the polarization-rotational angle θ and the mismatch m and on its rotational direction (i.e., clockwise or anticlockwise direction) that depends on the mode. Using the two-state model, we also discuss the angular momenta of the polarized light in the PhC waveguide, which are directly related to the Stokes parameters that characterize the polarization rotations.
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