Controlled Single-Cooper-Pair Charging Effects in a Small Josephson Junction Array
نویسندگان
چکیده
We report on measurements of single-Cooper-pair charging effects in small Josephson junction arrays, and the experimental techniques that were used. We succeeded in having complete control over the array’s electrostatic parameters; offset charges were accurately compensated, and the poisoning of 2e-periodic effects by quasiparticles was circumvented. This allowed for a controlled study of the array’s coherent ground state. A few measurements gave results which were not fully 2e-periodic due to interesting parity effects. The arrays are in the regime where the energy scales for the Josephson effect and single-charge effects are comparable.
منابع مشابه
Correlated transport through junction arrays in the small Josephson energy limit: incoherent Cooper-pairs and hot electrons
We study correlated transport in a Josephson junction array for small Josephson energies. In this regime transport is dominated by Cooper-pair hopping, although we observe that quasiparticles can not be neglected. We assume that the energy dissipated by a Cooper-pair is absorbed by the intrinsic impedance of the array. This allows us to formulate explicit Cooper-pair hopping rates without addin...
متن کاملCoulomb blockade and coherent single-cooper-pair tunneling in single Josephson junctions.
We have measured the current-voltage characteristics of small-capacitance single Josephson junctions at low temperatures ( T< or =0.04 K), where the strength of the coupling between the single junction and the electromagnetic environment was controlled with one-dimensional arrays of dc SQUIDs. We have clearly observed Coulomb blockade of Cooper-pair tunneling and even a region of negative diffe...
متن کاملdc conductivity of an array of Josephson junctions in the insulating state.
We consider microscopically low-temperature transport in weakly disordered arrays of Josephson junctions in the Coulomb blockade regime. We demonstrate that at sufficiently low temperatures the main contribution to the dc conductivity comes from the motion of single-Cooper-pair excitations, scattered by irregularities in the array. Being proportional to the concentration of the excitations, the...
متن کاملFluxonium: single cooper-pair circuit free of charge offsets.
The promise of single Cooper-pair quantum circuits based on tunnel junctions for metrology and quantum information applications is severely limited by the influence of offset charges: random, slowly drifting microscopic charges inherent in many solid-state systems. By shunting a small junction with the Josephson kinetic inductance of a series array of large-capacitance tunnel junctions, thereby...
متن کاملAntibunched Photons from Inelastic Cooper-Pair Tunneling.
We demonstrate theoretically that charge transport across a Josephson junction, voltage-biased through a resistive environment, produces antibunched photons. We develop a continuous-mode description of the emitted radiation field in a semi-infinite transmission line terminated by the Josephson junction. Within a perturbative treatment in powers of the tunneling coupling across the Josephson jun...
متن کامل