相关论文: Dephasing in Open Quantum Dots

We report magnetotransport measurements of two-dimensional holes in open quantum dots, patterned either as a single-dot or an array of dots, on a GaAs quantum well. For temperatures $T$ below 500 mK, we observe signatures of coherent…

The electron dephasing time $\tau_{\phi}$ in a diffusive quantum dot is calculated by considering the interaction between the electron and dynamical defects, modelled as two-level system. Using the standard tunneling model of glasses, we…

Conduction electrons in disordered metals and heavily doped semiconductors at low temperatures preserve their phase coherence for a long time: phase relaxation time $\tau_\phi$ can be orders of magnitude longer than the momentum relaxation…

We report measurements of the electron dephasing time extracted from the weak localization (WL) correction to the average conductance in an open AlGaAs/GaAs quantum dot from 1 K to 13 mK. In agreement with theoretical predictions but in…

We have measured the phase decoherence rate, $\tau_{\phi}^{-1}$ of conduction electrons in disordered Ag wires implanted with 2 and 10 parts per million Fe impurities, by means of the weak localization magnetoresistance. The Kondo…

The observation of coherent quantum transport phenomena in metals and semiconductors is limited by the eventual loss of phase coherence of the conducting electrons. We use the weak localization effect to measure the low-temperature…

The conduction electrons' dephasing rate, $\tau_{\phi}^{-1}$, is expected to vanish with the temperature. A very intriguing apparent saturation of this dephasing rate in several systems was recently reported at very low temperatures. The…

The low-temperature behavior of the electron phase coherence time, $\tau_{\phi}$, in mesoscopic metal wires has been a subject of controversy recently. Whereas theory predicts that $\tau_{\phi}(T)$ in narrow wires should increase as…

We report on measurements of the magnetoconductance of an open circular InGaAs quantum dot between 1.3K and 204K. We observe two types of magnetoconductance fluctuations: universal conductance fluctuations (UCFs), and 'focusing'…

We establish an explicit correspondence between perturbative and nonperturbative results in the problem of quantum decoherence in disordered conductors. We demonstrate that the dephasing time $\tau_{\phi}$ cannot be unambiguously extracted…

Ever since the first discoveries of the quantum-interference transport in mesoscopic systems, the electron dephasing times, $\tau_\phi$, in the concentrated AuPd alloys have been extensively measured. The samples were made from different…

We present measurements of the phase coherence time $\tau_\phi$ in six quasi-1D Au wires and clearly show that $\tau_\phi$ is temperature independent at low temperatures. We suggest that zero-point fluctuations of the intrinsic…

Temperature dependence of electron dephasing time $\tau_\phi(T)$ is calculated for a disordered metal with small concentration of superconductive grains. Above the macroscopic superconducting transition line, when electrons in the metal are…

We develop a new unified theoretical approach enabling us to non-perturbatively study the effect of electron-electron interactions on weak localization in arbitrary arrays of quantum dots. Our model embraces (i) weakly disordered conductors…

The dephasing time of electrons in open semiconductor quantum dots, measured using ballistic weak localization, is found to saturate below ~ 100 mK, roughly twice the electron base temperature, independent of dot size. Microwave radiation…

The temperature dependence of electron spin coherence in singly negatively charged (In,Ga)As/GaAs quantum dots is studied by time-resolved Faraday rotation. The decoherence time T2 is constant on a microsecond scale for temperatures below…

Temperature dependent weak localization is measured in metallic nanowires in a previously unexplored size regime down to width $w=5$ nm. The dephasing time, $\tau_{\phi}$, shows a low temperature $T$ dependence close to quasi-1D theoretical…

We calculate the dephasing time $\tau_{\phi}(B)$ of an electron in a two-dimensional quantum well with a Rashba spin-orbit interaction, spin-polarized by an arbitrarily large magnetic field parallel to the layer. $\tau_\phi (B)$ is…

We have systematically investigated the low-temperature electron dephasing times $\tau_\phi$ in more than 40 three-dimensional polycrystalline impure metals with distinct material characteristics. In all cases, a saturation of the dephasing…

We present measurements of the phase coherence time \tauphi in quasi one-dimensional Au/Fe Kondo wires and compare the temperature dependence of \tauphi with a recent theory of inelastic scattering from magnetic impurities (Phys. Rev. Lett.…