Directional light output from photonic-wire microcavity semiconductor lasers

Chaotic microcavity laser with high quality factor and unidirectional output

“…Cavity shape has been employed as a design parameter in optimizing microlaser performance, e.g. deformation from circularity to achieve anisotropic output [3,4,5], which is an easy and cost-effective way compared to waveguide coupling which requires accurate positioning of a waveguide next to or underneath the cavity [6,7,8]. However, deformed microdisk lasers produce output beams in multiple directions.…”

Micro-Optical Resonators for Microlasers and Integrated Optoelectronics

“…In wavelength-sized microresonator structures, semiconductor material luminescence can be either suppressed or enhanced, and they also enable narrowing of the spectral linewidth of the emitted light (Haroche, 1989;Yokoyama, 1992;Yamamoto, 1993;Vahala, 2003). Since 1946, when it was first proposed that the spontaneous emission from an excited state of an emitter can be significantly altered if it is placed into low-loss wavelength-scale cavity (Purcell, 1946), various microresonator designs for efficient control of spontaneous emission have been explored including microdisk Baba, 1997Baba, , 1999Backes, 1999;Cao, 2000;Fujita, 1999Fujita, , 2001Fujita, , 2002Zhang, 1996), microsphere Shopova, 2004;Rakovich, 2003) and micropost (Pelton, 2002;Reithmaier, 2004;Santori, 2004;Solomon, 2001;Gayral, 1998) resonators as well as PC defect cavities Boroditsky, 1999;Gayral, 1999). Depending on the Q-factors (resonance linewidths) of the modes supported by the microresonator in the spontaneous emission range of the resonator material, the two situations illustrated in Fig.…”

“…Recently proposed micro-toroidal resonators (Ilchenko, 2001;Vahala, 2003;Polman, 2004) not only demonstrate very high WG-mode Qfactors approaching those of microspheres but also enable reduction of WGmode volume, increase of resonator FSR, and on-chip integration with other components. Circular high-index-contrast microring and microdisk resonators based on planar waveguide technology with diameters as small as 1-10 μm are able to support strongly-confined WG modes with typical Q-factors of 10 4 -10 5 and are widely used as microlaser cavities Baba, 1997Baba, , 1999Cao, 2000;Zhang, 1996) and add/drop filters for WDM networks (Hagness, 1997;Little, 1997Little, , 1999Chin, 1999). Recently, record Q-factors have been demonstrated in wedge-edge microdisk resonators (Q in excess of 1 million, and in polished crystalline microcavities (Q>10 10 , Savchenkov, 2004).…”

“…It enables the index contrast to be adjusted by as much as 30% by changing the resonator material composition in between that of SiO 2 and Si 3 N 4 . Of course, GaAs, InP, and GaN-based semiconductors have attracted much attention as the materials for microresonator device fabrication (Baba, 1997;Hagness, 1997;Solomon, 2001;Gianordoli, 2000;Grover, 2001Zhang, 1996;Kneissl, 2004), as they enable very compact resonator structures that can perform passive (coupling, splitting and multiplexing) and active (light generation, amplification, detection, modulation) functions in the same material system. Most semiconductor microdisk and planar PC resonators consist of thin heterostructure layers.…”

“…Coupling to microsphere (Serpenguzel, 1995;Spillane, 2002) and microtoroid resonators through tapered fibres has several distinct advantages such as the built-in coupler alignment, relatively simple fabrication, possible on-chip integration, and control of the coupling efficiency by the change of the fibre thickness. However, integrated, waferfabricated microresonators are usually coupled into a photonic circuit through either planar (rib) waveguides (Hagness, 1997;Little, 1997Little, , 1999Chin, 1999;Zhang, 1996; or PC waveguides (Noda, 2000).…”