Stabilizing Rabi oscillation of a charge qubit via the atomic clock technique

• Main Authors: Yu, Deshui, Landra, Alessandro, Kwek, Leong Chuan, Amico, Luigi, Dumke, Rainer
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2018
• Subjects: Cooper-pair Box; Charge Qubit
• Online Access: https://hdl.handle.net/10356/89216; http://hdl.handle.net/10220/44820
• Institution: Nanyang Technological University

We propose a superconducting circuit-atom hybrid, where the Rabi oscillation of single excess Cooper pair in the island is stabilized via the common atomic clock technique. The noise in the superconducting circuit is mapped onto the voltage source which biases the Cooper-pair box via an inductor and a gate capacitor. The fast fluctuations of the gate charge are significantly suppressed by an inductor–capacitor resonator, leading to a long-relaxation-time Rabi oscillation. More importantly, the residual low-frequency fluctuations are further reduced by using the general feedback-control method, in which the voltage bias is stabilized via continuously measuring the dc-Stark-shift-induced atomic Ramsey signal. The stability and coherence time of the resulting charge-qubit Rabi oscillation are both enhanced. The principal structure of this Cooper-pair-box oscillator is studied in detail.