相关论文: Practical quantum realization of the ampere from t…

A crucial limit to measurement efficiencies of superconducting circuits comes from losses involved when coupling to an external quantum amplifier. Here, we realize a device circumventing this problem by directly embedding a two-level…

We demonstrate the synchronization of current quantization in a parallel array of weakly coupled Josephson Junctions operating in the regime of the coherent quantum phase slip. The first quantized current step on the voltage-current…

The quantum Josephson voltage standard is well established across the metrology community for many years. It relies on the synchronisation of the flux tunneling in the S/I/S Josepson junctions (JJ) with the microwave radiation (MW). The…

A silicon electron pump operating at the temperature of liquid helium has demonstrated repeatable operation with sub-ppm accuracy. The pump current, approximately 168 pA, is measured by three laboratories, and the measurements agree with…

Today, people are looking forward to get an awesome computational power. This kind of desire can be answered by quantum computing. By adopting quantum mechanics theory, it can generate a very fast computation result. As known, quantum…

Noisy voltage sources can be a limiting factor for fundamental physics experiments as well as for device applications in quantum information, mesoscopic circuits, magnetometry, and other fields. The best commercial DC voltage sources can be…

The quantized current generated by a quantum dot pump is calculated numerically. The numerical simulation is done by dividing the time varying potential into many static potentials with a short time interval and calculating the electron…

We tackle the problem of accurate simulations of switching currents arising from tunnel events in the washboard potentials associated to Josephson junctions. The measurements of the probability distribution of the switching currents is…

Using standard microfabrication techniques it is now possible to construct devices, which appear to reliably manipulate electrons one at a time. These devices have potential use as building blocks in quantum computing devices, or as a…

Amplifiers are crucial in every experiment carrying out a very sensitive measurement. However, they always degrade the information by adding noise. Quantum mechanics puts a limit on how small this degradation can be. Theoretically, the…

The quantum Hall effect (QHE) is a cornerstone in the new International System of Units (SI), wherein the base units are derived from seven fundamental constants such as Planck's constant h and elementary charge e. Graphene has…

The voltage oscillations which occur in an ideally current-biased Josephson junction, were proposed to make a current standard for metrology. We demonstrate similar oscillations in a more complex Josephson circuit derived from the Cooper…

There is no fundamental limit to the precision of a classical measurement. The position of a meter's needle can be determined with an arbitrarily small uncertainty. In the quantum realm, however, fundamental quantum fluctuations due to the…

Recent experimental demonstrations of quantum coherence of the charge and flux states of Josephson junctions show that the quantum Josephson dynamics can be used to develop scalable quantum logic circuits. In this work, I review the basic…

Quantum computation offers a promising new kind of information processing, where the non-classical features of quantum mechanics can be harnessed and exploited. A number of models of quantum computation exist, including the now well-studied…

By utilizing quantum mechanical effects, such as superposition and entanglement, quantum metrology promises higher precision than the classical strategies. It is, however, practically challenging to realize the quantum advantages. This is…

The revised International System of Units (SI), expected to be approved late in 2018, has implications for physics pedagogy; the ampere definition which dates from 1948 will be replaced by a definition that fixes the numerical value of the…

The generation of ac modulated quantized current waveforms using a semiconductor non-adiabatic single electron pump is demonstrated. In standard operation the single electron pump generates a quantized output current of I = ef where e is…

We present a robust method, based only on measurements, to produce superconducting cluster states. The measurement of the current of a few parallel Josephson-junction qubits realizes a novel type of quantum-state selector. Using this…

We measure current by counting single electrons tunneling through an InAs nanowire quantum dot. The charge detector is realized by fabricating a quantum point contact in close vicinity to the nanowire. The results based on electron counting…