ترغب بنشر مسار تعليمي؟ اضغط هنا

Experimental realization of a Coulomb blockade refrigerator

194   0   0.0 ( 0 )
 نشر من قبل Anna Feshchenko
 تاريخ النشر 2014
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

We present an experimental realization of a Coulomb blockade refrigerator (CBR) based on a single - electron transistor (SET). In the present structure, the SET island is interrupted by a superconducting inclusion to permit charge transport while preventing heat flow. At certain values of the bias and gate voltages, the current through the SET cools one of the junctions. The measurements follow theoretical model down to about 80 mK, which was the base temperature of the current measurements. The observed cooling increases rapidly with decreasing temperature in agreement with the theory, reaching about 15 mK drop at the base temperature. CBR appears as a promising electronic cooler at temperatures well below 100 mK.



قيم البحث

اقرأ أيضاً

We propose a remarkably simple electronic refrigerator based on the Coulomb barrier for single-electron tunneling. A fully normal single-electron transistor is voltage $V$ biased at a gate position such that tunneling through one of the junctions cos ts an energy of about $k_BT ll eV, E_C$, where $T$ is the temperature and $E_C$ is the transistor charging energy. The tunneling in the junction with positive energy cost cools both the electrodes attached to it. Immediate practical realizations of such a refrigerator make use of Andreev mirrors which suppress heat current while maintaining full electric contact.
Two strongly coupled quantum dots are theoretically and experimentally investigated. In the conductance measurements of a GaAs based low-dimensional system additional features to the Coulomb blockade have been detected at low temperatures. These regi ons of finite conductivity are compared with theoretical investigations of a strongly coupled quantum dot system and good agreement of the theoretical and the experimental results has been found.
We observed the recently predicted quantum suppression of dynamical Coulomb blockade on short coherent conductors by measuring the conductance of a quantum point contact embedded in a tunable on-chip circuit. Taking advantage of the circuit modularit y we measured most parameters used by the theory. This allowed us to perform a reliable and quantitative experimental test of the theory. Dynamical Coulomb blockade corrections, probed up to the second conductance plateau of the quantum point contact, are found to be accurately normalized by the same Fano factor as quantum shot noise, in excellent agreement with the theoretical predictions.
178 - P. Pingue 2004
A tunable directional coupler based on Coulomb Blockade effect is presented. Two electron waveguides are coupled by a quantum dot to an injector waveguide. Electron confinement is obtained by surface Schottky gates on single GaAs/AlGaAs heterojunctio n. Magneto-electrical measurements down to 350 mK are presented and large transconductance oscillations are reported on both outputs up to 4.2 K. Experimental results are interpreted in terms of Coulomb Blockade effect and the relevance of the present design strategy for the implementation of an electronic multiplexer is underlined.
We consider the ground-state energy and the spectrum of the low-energy excitations of a Majorana island formed of topological superconductors connected by a single-mode junction of arbitrary transmission. Coulomb blockade results in $e$-periodic modu lation of the energies with the gate-induced charge. We find the amplitude of modulation as a function of reflection coefficient ${cal R}$. The amplitude scales as $sqrt{cal R}$ in the limit ${cal R}to 0$. At larger ${cal R}$, the dependence of the amplitude on the Josephson and charging energies is similar to that of a conventional-superconductor Cooper-pair box. The crossover value of ${cal R}$ is small and depends on the ratio of the charging energy to superconducting gap.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا