Assessment of VCSEL thermal rollover mechanisms from measurements and empirical modeling
Artikel i vetenskaplig tidskrift, 2011

We use an empirical model together with experimental measurements for studying mechanisms contributing to thermal rollover in vertical-cavity surface-emitting lasers (VCSELs). The model is based on extraction of the temperature dependence of threshold current, internal quantum efficiency, internal optical loss, series resistance and thermal impedance from measurements of output power, voltage and lasing wavelength as a function of bias current over an ambient temperature range of 15-100 degrees C. We apply the model to an oxide-confined, 850-nm VCSEL, fabricated with a 9-mu m inner-aperture diameter and optimized for highspeed operation, and show for this specific device that power dissipation due to linear power dissipation (sum total of optical absorption, carrier thermalization, carrier leakage and spontaneous carrier recombination) exceeds power dissipation across the series resistance (quadratic power dissipation) at any ambient temperature and bias current. We further show that the dominant contributors to self-heating for this particular VCSEL are quadratic power dissipation, internal optical loss, and carrier leakage. A rapid reduction of the internal quantum efficiency at high bias currents (resulting in high temperatures) is identified as being the major cause of thermal rollover. Our method is applicable to any VCSEL and is useful for identifying the mechanisms limiting the thermal performance of the device and to formulate design strategies to ameliorate them.

performance

surface-emitting lasers

power

active-region

Författare

P. P. Baveja

Chalmers University of Technology

University of Rochester Institute of Optics

Benjamin Kögel

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Petter Westbergh

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Johan Gustavsson

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Åsa Haglund

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

D. N. Maywar

Rochester Institute of Technology

G. P. Agrawal

University of Rochester Institute of Optics

Anders Larsson

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Optics Express

1094-4087 (ISSN)

Vol. 19 16 15490-15505

Styrkeområden

Informations- och kommunikationsteknik

Ämneskategorier

Fysik

DOI

10.1364/OE.19.015490