Coulomb blockade electrometer with a high-Tc island
Kubatkin S.E., Tzalenchuk A.Ya., Ivanov Z.G., Delsing P., Shekhter R.I., Claeson T.
We report on a successful attempt to fabricate a Coulomb blockade electrometer consisting of an ultrasmall õ÷ÁÇóÉÚ07_$ (YBCO) island coupled to two gold electrodes through high-resistance native surfactt tunnel barrier. A third electrode placed near the island was used as an electrostatic gate. Spectra typical for tunnelling into the YBCO superconductor were reproducibly measured. At temperatures below 0.5 ë the low bias conductance was suppressed by the Coulomb blockade. The blockade could be periodically varied by the gate potential. An external magnetic field of up to 5 Τ strongly influenced the transport via the island but without any change in the period of the Coulomb oscillations. PACS 74.50+r; 73.40.Gk; 73.40.Rw; 73.20.Dx