19.2 Microscopic Resonators
505
Fig. 19.24 Strong coupling of a single QD exciton (due to monolayer fluctuation in a 13 ML thick GaAs/Al 0.33 Ga 0.67 As
QW) with a WGM in a microdisk of 2 µm diameter (inset). (a) Anti-crossing of upper and lower peak for various
temperatures. Symbols are data points, solid lines are theory considering coupling. The dashed (dash-dotted) line is the
expected temperature shift of the WGM mode (exciton energy). (b) Photoluminescence spectrum at the anti-crossing
point (T = 30 K). Experimental data (squares) and fit with two peaks (solid line). Adapted from [1648]
(a)
(b)
6
5
4
3
2
1
0
0
5 10 15 20 25 30 35
P
0 /
Fig. 19.25 a Micropillar with MBE-grown GaAs/AlAs DBRs and a cavity containing five layers of InAs quantum dots
as indicated. The pillar has been prepared by reactive ion etching. Reprinted with permission from [1650], ©1998 APS.
b Experimental decay time τ of on-resonance quantum dot luminescence scaled by off-resonance lifetime τ 0 = 1.1 ns
(close to lifetime in a QD in bulk) for a variety of micropillars with different Purcell factors F P . The error bars correspond
to the measurement accuracy of the decay time (±70 ps), the dashed line is a guide to the eye. Adapted from [1650]
10
4 . In order to couple light out of such a disc, deformed resonators, e.g. with a defect in the form of
protrusions [1646], were devised. Deformed resonators are discussed in more detail in the next section.
The strong coupling of a QD exciton to a whispering gallery mode is shown in Fig. 19.24 where
anti-crossing behavior is observed at low temperatures. Tuning is achieved by temperature variation.
Behavior of a similar system in the weak coupling regime is shown in Fig. 19.26.
505
Fig. 19.24 Strong coupling of a single QD exciton (due to monolayer fluctuation in a 13 ML thick GaAs/Al 0.33 Ga 0.67 As
QW) with a WGM in a microdisk of 2 µm diameter (inset). (a) Anti-crossing of upper and lower peak for various
temperatures. Symbols are data points, solid lines are theory considering coupling. The dashed (dash-dotted) line is the
expected temperature shift of the WGM mode (exciton energy). (b) Photoluminescence spectrum at the anti-crossing
point (T = 30 K). Experimental data (squares) and fit with two peaks (solid line). Adapted from [1648]
(a)
(b)
6
5
4
3
2
1
0
0
5 10 15 20 25 30 35
P
0 /
Fig. 19.25 a Micropillar with MBE-grown GaAs/AlAs DBRs and a cavity containing five layers of InAs quantum dots
as indicated. The pillar has been prepared by reactive ion etching. Reprinted with permission from [1650], ©1998 APS.
b Experimental decay time τ of on-resonance quantum dot luminescence scaled by off-resonance lifetime τ 0 = 1.1 ns
(close to lifetime in a QD in bulk) for a variety of micropillars with different Purcell factors F P . The error bars correspond
to the measurement accuracy of the decay time (±70 ps), the dashed line is a guide to the eye. Adapted from [1650]
10
4 . In order to couple light out of such a disc, deformed resonators, e.g. with a defect in the form of
protrusions [1646], were devised. Deformed resonators are discussed in more detail in the next section.
The strong coupling of a QD exciton to a whispering gallery mode is shown in Fig. 19.24 where
anti-crossing behavior is observed at low temperatures. Tuning is achieved by temperature variation.
Behavior of a similar system in the weak coupling regime is shown in Fig. 19.26.