Crossover from single electron counting to Cooper pair counting

S.K. Adhikari, M. Casas, A. Puente +6 more

Rafael Mendoza, Mauricio Fortes, MANUEL DE LLANO +1 more

Akio Tokumitu, Kazumasa Miyake, Kazuo Yamada

The problem on crossover between the Cooper-pair condensation and the Bose-Einstein condensation of “di-electronic molecules” in two-dimensional superconductors is discussed. a result based on the Nozières and Schmitt-Rink formalism is reviewed and a preliminary result beyond their formalism is presented. In the latter, effect of repulsion between electron pairs due to the exchange effect among constituent electrons plays a crucial role.

Jutarat Tanarom, Ploybussara Gomasang

The characteristics of the single Cooper pair transistor, a key component of single-charge electronics that manipulates single or Cooper pair electrons via the Coulomb blockade phenomenon, are discussed in this article. Due to these characteristics, the single Cooper pair transistor plays an important role in metrology such as sensitive electrometry and quantum computing. Electron beam lithography and electron gun evaporation are used to fabricate the single Cooper pair transistor. The measurement is performed at lower temperatures than 100 mK by using a dilution refrigerator. It has been found that only the tunneling of Cooper pairs of electrons is shown by the relationship between the gate voltage and the supercurrent. It indicates that a single Cooper pair transistor can be used as a sensitive sensor when integrated into other devices, exhibiting the tunneling properties of Cooper pairs at 16 GHz.

G. Potel, Ricardo A. Broglia

Wanyin Cui