Photonic bandgap crystal InGaAsP membrane microresonators (original) (raw)

InGaAsP photonic band gap crystal membrane microresonators

Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures

We have microfabricated two-dimensional ͑2D͒ photonic band gap structures in a thin slab of dielectric material to define reflectors and high-Q microresonators. By selectively omitting holes from the 2D photonic crystal, optical microcavities, and in-plane microresonator switches can be defined. We have designed this structure with a finite difference time domain approach, and demonstrate the effect of lithographic 2D band gap tuning on the emission spectra of InGaAs/ InGaAsP multiple quantum well material emission wavelength of 1.55 m.

In-plane microcavity resonators with two-dimensional photonic bandgap mirrors

IEE Proceedings - Optoelectronics, 1998

Two-dimensional photonic bandgap structures are used to form one-dimensional microcavities in a GaAsIAlGaAs laser-like heterostructure. Photoluminescence from InAs quantum dots embedded in the optical waveguide is used to probe these cavities. At resonance, peak transmission values greater than 30% are observed for modes of 8nm half-width, associated with estimated reflectivities in excess of 90%. The mode volume is limited by the penetration depth of the field into the PBG mirrors, which amounts to approximately one lattice spacing or 0.25pm. This value of penetration depth approaches the ultimate limit on compactness that can be achieved with the particular photonic lattice parameters used in the experiments. The dependence of the resonance wavelength on cavity length compares satisfactorily with a theoretical supercell model.

Coupled optical microcavities in one-dimensional photonic bandgap structures

Journal of Optics-nouvelle Revue D Optique, 2001

We present a detailed theoretical and experimental study of the evanescent coupled optical microcavity modes in one-dimensional photonic bandgap structures. The coupled-cavity samples are fabricated by depositing alternating hydrogenated amorphous silicon nitride and silicon oxide layers. Splitting of the eigenmodes and formation of a defect band due to interaction between the neighbouring localized cavity modes are experimentally observed. Corresponding field patterns and the transmission spectra are obtained by using transfer matrix method (TMM) simulations. A theoretical model based on the classical wave analogue of the tight-binding (TB) picture is developed and applied to these structures. Experimental results are in good agreement with the predictions of the TB approximation and the TMM simulations.

Surface state photonic bandgap cavities

We propose and analyze a new type of a resonant high-Q cavity for lasing, sensing or filtering applications, which is based on a surface states of a finite photonic crystal. We demonstrate that such the cavity can have a Q factor comparable with that one of conventional photonic band-gap defect mode cavities. At the same time, the distinguished feature of the surface mode cavity is that it is situated directly at the surface of the photonic crystal. This might open up new possibilities for design of novel photonic devices and integration of photonic circuits.

Experimental demonstration of a high quality factor photonic crystal microcavity

Applied Physics Letters, 2003

Sub-threshold measurements of a photonic crystal (PC) microcavity laser operating at 1.3 µm show a linewidth of 0.10 nm, corresponding to a quality factor (Q) ∼ 1.3x10 4 . The PC microcavity mode is a donor-type mode in a graded square lattice of air holes, with a theoretical Q ∼ 10 5 and mode volume V eff ∼ 0.25 cubic half-wavelengths in air. Devices are fabricated in an InAsP/InGaAsP multi-quantum well membrane and are optically pumped at 830 nm. External peak pump power laser thresholds as low as 100 µW are also observed.

Frequency control of photonic crystal membrane resonators by monolayer deposition

Applied Physics Letters, 2006

We study the response of GaAs photonic crystal membrane resonators to thin film deposition. Slow spectral shifts of the cavity mode of several nanometers are observed at low temperatures, caused by cryo-gettering of background molecules. Heating the membrane resets the drift and shielding will prevent drift altogether. In order to explore the drift as a tool to detect surface layers, or to intentionally shift the cavity resonance frequency, we studied the effect of self-assembled monolayers of polypeptide molecules attached to the membranes. The 2 nm thick monolayers lead to a discrete step in the resonance frequency and partially passivate the surface.

Room temperature photonic crystal defect lasers at near-infrared wavelengths in InGaAsP

Journal of Lightwave Technology, 1999

Room temperature lasing from optically pumped single defects in a two-dimensional (2-D) photonic bandgap (PBG) crystal is demonstrated. The high-Q optical microcavities are formed by etching a triangular array of air holes into a halfwavelength thick multiquantum-well waveguide. Defects in the 2-D photonic crystal are used to support highly localized optical modes with volumes ranging from 2 to 3 (/2n) 3. Lithographic tuning of the air hole radius and the lattice spacing are used to match the cavity wavelength to the quantum-well gain peak, as well as to increase the cavity Q. The defect lasers were pumped with 10-30 ns pulses of 0.4 01% duty cycle. The threshold pump power was 1.5 mW (500 W absorbed).

Design of Ultrahigh- $Q$ 1-D Photonic Crystal Microcavities

IEEE Journal of Quantum Electronics, 2009

Waveguide based 1-D photonic crystal (PC) microcavities in silicon-on-insulator are investigated by 2-D finite-difference time-domain method. Values up to 6 7 10 6 for the quality factor () are feasible if the cavities are properly designed. The factors that govern are analyzed in both real space and momentum space. Etching down into the SiO 2 layer is found to give more than 20% improvement in compared to the structure in which etching is stopped at the oxide layer. Short air gap mirrors are used to reduce the vertical scattering loss. The addition to the Bragg mirrors of tapered periods optimized to produce a cavity mode with a near Gaussian shaped envelope results in a major reduction in vertical loss. A new tapered structure with varying Si block width demonstrates an ultrahigh-and relieves the fabrication constraints compared to the conventional air slots tapered structure.