Patent ID: 10193310

Abstract:
A low power, side-emitting semiconductor laser diode is provided. The laser diode is formed from a semiconductor heterostructure having an active layer sandwiched between an n-type layer and a p-type layer, wherein the active layer forms a gain medium of width W. Front and back reflectors of reflectivity Rf and Rb are arranged on opposing side facets of the semiconductor heterostructure part to form a cavity of length L containing at least a part of the active layer which thus forms the gain medium for the laser diode, the gain medium having an internal loss αi. To achieve stable, low power operation close to threshold, the laser diode is configured with the following parameter combination: width W: 1 μm≤W≤2 μm; cavity length L: 100 μm≤L≤600 μm; internal loss αi: 0 cm−1≤αi≤30 cm−1; back reflectivity Rb: 100≥Rb≥80%; and front reflectivity Rf: 100≥Rf≥60%.