Spatially and spectrally resolved measurement of optical loss in InGaN laser structures

• Published in: Journal of crystal growth Vol. 230; no. 3; pp. 517 - 521
• Main Authors: Summers, H.D., Smowton, P.M., Blood, P., Dineen, M., Perks, R.M., Bour, D.P., Kneissel, M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.2001; Elsevier
• Subjects: A3. Quantum wells; B1. Nitrides; B3. Laser diodes; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Lasers; Optics; Physics; Semiconductor lasers; laser diodes; 42.25.B; A3. Quantum wells; B3. Laser diodes; 42.55.P; B1. Nitrides; 78.40.F; Optical losses; Blue lasers; Semiconductor lasers; Spectral resolution; Gallium nitrides; Ternary compounds; Visible radiation; Quantum well lasers; Indium nitrides; Experimental study; Laser diodes; Spatial resolution
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/S0022-0248(01)01284-2

The optical loss co-efficient in InGaN laser diodes, emitting at ∼410 nm, has been measured. The measurement technique is based on the transmission of internally generated spontaneous emission through varying lengths of the laser waveguide. It is unique in that it provides spectral and spatial information on the optical loss. The lasers studied are typical of InGaN structures showing a high degree of waveguide loss, α i =40 cm −1 . The measurements also show clear evidence of higher order transverse modes in the direction perpendicular to the growth plane with resonant leakage of the optical field into the outer layers of the structure. This produces a modulation in the loss of these modes.