Abstract
Optical intersubband response of a multiple quantum well (MQW)-embedded microcavity driven by a coherent pump field is studied theoretically. The n-type doped MQW structure with three subbands in the conduction band is sandwiched between a semi-infinite medium and a distributed Bragg reflector (DBR). A strong pump field couples the two upper subbands and a weak field probes the two lower subbands. To describe the optical response of the MQW-embedded microcavity, we adopt a semi-classical nonlocal response theory. Taking into account the pump-probe interaction, we derive the probe-induced current density associated with intersubband transitions from the single-particle density-matrix formalism. By incorporating the current density into the Maxwell equation, we solve the probe local field exactly by means of Green's function technique and the transfer-matrix method. We obtain an exact expression for the probe absorption coefficient of the microcavity. For a GaAs/Al xGa 1-xAs MQW structure sandwiched between a GaAs/AlAs DBR and vacuum, we performed numerical calculations of the probe absorption spectra for different parameters such as pump intensity, pump detuning, and cavity length. We find that the probe spectrum is strongly dependent on these parameters. In particular, we find that the combination of the cavity effect and the Autler-Townes effect results in a triplet in the optical spectrum of the MQW system. The optical absorption peak value and its location can be feasibly controlled by varying the pump intensity and detuning.
Original language | English (US) |
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Title of host publication | Proceedings of SPIE - The International Society for Optical Engineering |
Publisher | Society of Photo-Optical Instrumentation Engineers |
Volume | 3944 |
State | Published - 2000 |
Externally published | Yes |
Event | Physics and Simulation of Optoelectronic Devices VIII - San Jose, CA, USA Duration: Jan 24 2000 → Jan 28 2000 |
Other
Other | Physics and Simulation of Optoelectronic Devices VIII |
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City | San Jose, CA, USA |
Period | 1/24/00 → 1/28/00 |
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Condensed Matter Physics