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Updated: Aug 12, 2026

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
Measurement of the excited-state lifetime of a microelectronic circuit
K W Lehnert1, K Bladh, L F Spietz
1Department of Applied Physics and Physics, Yale University, New Haven, Connecticut 06511, USA. konrad.lehnert@yale.edu
Abstract:
We demonstrate that a continuously measured microelectronic circuit, the Cooper-pair box measured by a radio-frequency single-electron transistor, approximates a quantum two-level system. We extract the Hamiltonian of the circuit through resonant spectroscopy and measure the excited-state lifetime. The lifetime is more than 10(5) times longer than the inverse transition frequency of the two-level system, even though the measurement is active. This lifetime is also comparable to an estimate of the known upper limit, set by spontaneous emission, for this circuit.
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