In this chapter we outline major principles of vertical-cavity surfaceemitting laser (VCSEL) design and operation. Basic device properties and generally applicable cavity design rules are introduced. Characteristic parameters like threshold gain and current, differential quantum efficiency and power conversion efficiency, as well as thermal resistance are discussed. We describe the design of Bragg reflectors and explain the transfer matrix method as a convenient tool to compute VCSEL resonator properties in a one-dimensional approximation. Experimental results illustrate the emission characteristics of high-efficiency VCSELs that apply selective oxidation for current and photon confinement. Both the 850 and 980 nm wavelength regions are considered. The basic treatment of laser dynamics and noise behavior is presented in terms of the small-signal modulation response as well as the relative intensity noise. Finally we give some examples of VCSEL applications in fiber-based optical interconnects, i.e., optical data transmission over short distances.
IntroductionVCSELs have undergone an extraordinary evolution over the past three decades. Suggested by Prof. Kenichi Iga and first demonstrated by the research group at Tokyo Institute of Technology in the late 1970s [1-3], VCSELs are a commodity item today [4] and already serve millions of computer users as the key component in modern navigation devices such as the optical mouse. In even larger quantity, this laser type has entirely replaced edge-emitting laser diodes for use in multimode fiber-based Gbit/s speed optical data transmission in premises networks and for the interconnection of various kinds of computer clusters. Several books entirely devoted R. Michalzik (B)