Phase-Controlled Apertures Using Heterodyne Optical Phase-Locked Loops |
| |
Authors: | Satyan N Wei Liang Aflatouni F Yariv A Kewitsch A Rakuljic G Hashemi H |
| |
Affiliation: | Dept. of Electr. Eng., California Inst. of Technol., Pasadena, CA; |
| |
Abstract: | In this letter, we demonstrate the use of an electronic feedback scheme using a voltage controlled oscillator (VCO) to control the optical phase of individual semiconductor lasers (SCLs) phase locked to a common reference laser using heterodyne optical phase-locked loops (OPLLs). The outputs of two external cavity SCLs phase-locked to a common reference laser are coherently combined, and the variation in the relative optical path lengths of the combining beams is corrected by dynamically changing the phase of the offset radio-frequency signal fed into one of the OPLLs by means of a VCO. A stable power combination efficiency of 94% is achieved. This inherently different method of phase control, i.e., electronic rather than the use of electrooptic crystals, is deemed essential for new applications involving coherent optoelectronics. |
| |
Keywords: | |
|
|