Quantum single-particle generator and shot noise in mesoscopic systems

Eugene V. Sukhorukov, Andrew N. Jordan

Μ. Büttiker, Peter Samuelsson

Theory predicts that electrons emitted from independent electron sources (metallic contacts) can nevertheless interfere. This interference is manifest in an exchange contribution to the shot noise correlation of currents at different contacts of a mesoscopic conductor. A geometry has been proposed in which second order (single particle) interference due to superposition of amplitudes is absent but fourth order (two-particle) interference exhibits Aharonov-Bohm oscillations. Recently such a geometry has been realized in an experiment and the theoretically predicted two-particle Aharonov-Bohm effect has been detected. We discuss Bell measurements and quantum state tomography using shot noise correlations. We discuss in addition structures in which two-particle interference effects are generated dynamically by varying electrostatic potentials with the help of gates or by generating electron-hole pairs by irradiating contacts of a mesoscopic conductor. These examples emphasize that two-particle processes are not related to a particular geometry but are a general feature of multiparticle observables like shot noise correlations.

Μ. Büttiker, Peter Samuelsson

Abstract Theory predicts that electrons emitted from independent electron sources (metallic contacts) can nevertheless interfere. This interference is manifest in an exchange contribution to the shot noise correlation of currents at different contacts of a mesoscopic conductor. A geometry has been proposed in which second order (single particle) interference due to superposition of amplitudes is absent but fourth order (two‐particle) interference exhibits Aharonov‐Bohm oscillations. Recently such a geometry has been realized in an experiment and the theoretically predicted two‐particle Aharonov‐Bohm effect has been detected. We discuss Bell measurements and quantum state tomography using shot noise correlations. We discuss in addition structures in which two‐particle interference effects are generated dynamically by varying electrostatic potentials with the help of gates or by generating electron‐hole pairs by irradiating contacts of a mesoscopic conductor. These examples emphasize that two‐particle processes are not related to a particular geometry but are a general feature of multiparticle observables like shot noise correlations.

D. C. Glattli

Masayuki Hashisaka, Yoshiaki Yamauchi, Shuji Nakamura +3 more

We demonstrate a scheme to detect the quantum shot noise in coupled mesoscopic systems. By applying the noise thermometry to the capacitively coupled quantum point contacts (QPCs) we prove that the noise temperature of one QPC is in perfect proportion to that of the other QPC which is driven to nonequilibrium to generate quantum shot noise. The present mesoscopic bolometry, which is sensitive to the energy flow of $\ensuremath{\sim}1\text{ }\text{fW}$, allows us to detect the energy exchange between quantum systems at finite frequency and can also be applied for diverse precise measurements.