TY - JOUR

T1 - Superconducting single-Cooper-pair box as quantum bit

AU - Tsai, Jaw-Shen

AU - Nakamura, Y.

AU - Pashkin, Yuri

PY - 2001/9

Y1 - 2001/9

N2 - We demonstrated the first electronic control of 1-qubit achieved in a solid-state device by using a submicron electron device called a single-Cooper-pair box. The number of electrons in the box (typically 108) is quantized and they form a single macroscopic quantum charge-number state, corresponding to the number of excess electrons in the box. By making all the electrodes superconducting, we can couple two neighboring charge-number states coherently. In this way one can create an artificial two-level system. We attached an additional tunneling probe to the box to monitor the probability of one of the two states involved in the coherence. We applied a sufficiently fast voltage pulse to the gate to create a degenerated charge-number state, so that to force the two states to undergo a quantum oscillation. As a result, we indeed observed the coherent oscillation. This was the first time that the quantum coherent oscillation was observed in a solid-state device whose quantum states involved a macroscopic number of quantum particles. Multiple-pulse experiments were also carried out.

AB - We demonstrated the first electronic control of 1-qubit achieved in a solid-state device by using a submicron electron device called a single-Cooper-pair box. The number of electrons in the box (typically 108) is quantized and they form a single macroscopic quantum charge-number state, corresponding to the number of excess electrons in the box. By making all the electrodes superconducting, we can couple two neighboring charge-number states coherently. In this way one can create an artificial two-level system. We attached an additional tunneling probe to the box to monitor the probability of one of the two states involved in the coherence. We applied a sufficiently fast voltage pulse to the gate to create a degenerated charge-number state, so that to force the two states to undergo a quantum oscillation. As a result, we indeed observed the coherent oscillation. This was the first time that the quantum coherent oscillation was observed in a solid-state device whose quantum states involved a macroscopic number of quantum particles. Multiple-pulse experiments were also carried out.

KW - Quantum bit

KW - Quantum computing

KW - Single-electron box

KW - Single-Cooper-pair box

KW - Aluminum

U2 - 10.1016/S0921-4534(01)00172-1

DO - 10.1016/S0921-4534(01)00172-1

M3 - Journal article

VL - 357-360

SP - 1

EP - 6

JO - Physica C: Superconductivity and its Applications

JF - Physica C: Superconductivity and its Applications

SN - 0921-4534

IS - 4

ER -