Supplementary Information
Single-photon property characterization of 1.3 μm emissions from
InAs/GaAs quantum dots using silicon avalanche photodiodes
P. Y. Zhou, X. M. Dou, X. F. Wu, K. Ding, M. F. Li, H. Q. Ni, Z. C. Niu, D. S. Jiang, B. Q. Sun*
State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese
Academy of Sciences, P.O. Box 912, Beijing 100083, China
*Email: bqsun@semi.ac.cn
1. Spectra of ensemble InAs QDs under different pressures between 0 and 6 GPa
Figure S1. (a)-(g) PL spectra of 1.3 μm ensemble QDs under different pressures from 0 to 6 GPa.
The grey line in each graph indicates the luminescence peak we traced.
2. Setup response function for the time-resolved measurements using silicon APD
Figure S2. Setup response function (SRF) for the time-resolved measurements using silicon APD
(black line) and a 63 ps laser pulse diode. The setup resolution was obtained from the full width at
half maximum (FWHM) of the SRF, which is approximately 0.4 ns.
3. The lifetime of InAs QDs luminescence under different pressure
Figure S3. Lifetime of InAs QDs (with 0.9 μm emissions at 0 GPa and without cavity) under
different pressure from 0 to 3.25 GPa.
4. Setup response function for the time-resolved measurements using InGaAs APD
Figure S4. SRF for the time-resolved measurements using InGaAs APD (black line). The setup
resolution, obtained from the FWHM of the SRF, is approximately 0.44 ns.
Due to the mismatch between the wavelength (640 nm, 63 ps pulses) of diode laser (used to excite
QDs) and the InGaAs APD spectral response range, the setup resolution was measured using a
mode-locked Ti:sapphire laser with a width of ~0.1 ps pulses, and a wavelength of 980 nm.
5. Row data, background and correlation results of the g(2)(τ) measurements of a single InAs
QD at 0 GPa
Figure S5. Raw data, background and correlation results of the g(2)(τ) measurements for a single
InAs QD with 1331.9 nm emission line mentioned in the text under the condition of the dead time of
the used InGaAs APDs set to 1 (a) or 10 μs (b), respectively. The correlation results were obtained
by subtracting background from the raw data.
6. Spectra and g(2)(τ) measurements of a single QD (with ~900 nm emission at 0 GPa) under
different pressure from 0 to 3 GPa
Figure S6. (a)-(e) PL spectra of a single InAs QD (with ~900 nm emission line at 0 GPa) under
pressures of 0.85, 1.37, 1.72, 1.23 and 3.10 GPa, respectively, at 4 K; the inner panels are the
corresponding g(2)(τ) measurement results, red lines are fitting curve obtained from the similar
simulation of Reference (1).
To gain insight on how the pressure conditions affect the single-photon property of InAs QDs, and
to verify the new approach proposed more convincingly, we used a pressure device which can be
adjusted continuously among ~3 GPa range using a piezoelectric ceramic at low temperature,
monitored the QD PL spectra and the g(2)(τ) measurement evolution, where the QD emission line at 0
GPa is ~900 nm. Figures S5 (a)-(e) present the PL spectra and g(2)(τ) results obtained at five different
pressures. From these measurements it can be seen that, although the PL emission peak shifts to the
shorter wavelength, all g(2)(0) values are smaller than 0.3, indicating it remains the single-photon
emission under pressure.
(1) Nakajima, H.; Kumano, H.; Iijima, H.; Suemune, I. Appl. Phys. Lett. 2012, 101, 161107.