Abstract
We present investigations on coherent coupling of surface emitting quantum cascade lasers (QCLs). For this purpose, the evanescent field coupling method is exploited under incorporation of a ring cavity surface emitting QCL pair with an emission wavelength of ≈8 μm. A series of these pairs with intercavity separations of 1 and 3 μm was fabricated. The coupling gap of 1 μm yields robust phase-locked light source pairs with coherent emission at all injection currents and a corresponding threshold current density of 2.65 kA/cm2 at room-temperature.
| Original language | English (US) |
|---|---|
| Article number | 071103 |
| Journal | Applied Physics Letters |
| Volume | 97 |
| Issue number | 7 |
| DOIs | |
| State | Published - Aug 16 2010 |
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)