Electro-optical resonance modulation of vertical-cavity surface-emitting lasers.

Optical and electrical investigations of vertical-cavity surface-emitting lasers (VCSEL) with a monolithically integrated electro-optical modulator (EOM) allow for a detailed physical understanding of this complex compound cavity laser system. The EOM VCSEL light output is investigated to identify optimal working points. An electro-optic resonance feature triggered by the quantum confined Stark effect is used to modulate individual VCSEL modes by more than 20 dB with an extremely small EOM voltage change of less than 100 mV. Spectral mode analysis reveals modulation of higher order modes and very low wavelength chirp of < 0.5 nm. Dynamic experiments and simulation predict an intrinsic bandwidth of the EOM VCSEL exceeding 50 GHz.

Polarization switching and polarization mode hopping in quantum dot vertical-cavity surface-emitting lasers.

We show experimentally that polarization mode hopping in quantum dot vertical cavity surface emitting lasers (VCSELs) takes place between nonorthogonal elliptically polarized modes. In contrast to quantum well VCSELs the average dwell time decreases with injection current. This decrease is by 8 orders of magnitude: from seconds to nanoseconds and is achieved without any modifications of the VCSEL internal anisotropies. The observed scaling happens in a range of currents as wide as 8 times the threshold value.

Metal-cavity surface-emitting microlaser with hybrid metal-DBR reflectors.

We demonstrate a metal-cavity surface-emitting microlaser at room temperature using hybrid metal/distributed Bragg reflectors as well as substrate removal. Our devices operate under continuous-wave current injection at room temperature. The smallest laser is 1.0 µm in radius and ~4.0 µm in height with a circular beam shape and an output over 8 µW. The device lases at 995 nm wavelength with a threshold current of about 2.6 mA.

22-Gb/s Long Wavelength VCSELs.

1.55-microm vertical cavity surface-emitting low-parasitic lasers show open eyes up to 22-Gb/s modulation speed. Uncooled error-free operation over a wide temperature range up to 85 degrees C under constant bias conditions is demonstrated at 12.5-Gb/s data rate. At these fixed bias conditions the laser characteristics are practically invariant with temperature. These are the highest data-rates reported from a long-wavelength VCSEL structure to date.