Photoionization detection of a single Er$^{3+}$ ion with sub-100-ns time resolution

TL;DR

This paper demonstrates a high-speed, sensitive electrical detection method for single Er$^{3+}$ ions in silicon using RF reflectometry, enabling sub-100-ns resolution and first measurement of their excited state lifetime.

Contribution

The work introduces a novel RF reflectometry technique for fast, electrical detection of single optical centers in solids, achieving sub-100-ns resolution and measuring Er$^{3+}$ ion lifetime.

Findings

Achieved sub-100-ns time resolution in detecting photoionization.

Measured the excited state lifetime of a single Er$^{3+}$ ion as 0.49 μs.

Demonstrated potential for scalable, multi-channel quantum system readout.

Abstract

Efficient detection of single optical centers in solids is essential for quantum information processing, sensing, and single-photon generation applications. In this work, we use radio-frequency (RF) reflectometry to electrically detect the photoionization induced by a single Er$^{3+}$ ion in Si. The high bandwidth and sensitivity of the RF reflectometry provide sub-100-ns time resolution for the photoionization detection. With this technique, the optically excited state lifetime of a single Er$^{3+}$ ion in a Si nano-transistor is measured for the first time to be 0.49 $\pm$ 0.04 $\mu$s. Our results demonstrate an efficient approach for detecting a charge state change induced by Er excitation and relaxation. This approach could be used for fast readout of other single optical centers in solids and is attractive for large-scale integrated optical quantum systems thanks to the multi-channel RF reflectometry demonstrated with frequency multiplexing techniques.