Portal de Periódicos da CAPES

<title>Extremely short external-cavity lasers: direct semiconductor laser readout modeling by using finite difference time domain calculations</title>

2001; SPIE; Volume: 4595; Linguagem: Inglês

10.1117/12.446606

1996-756X

Janne K. Aikio, Kari Kataja, Dennis G. Howe,

Photonic and Optical Devices

In this paper we describe how finite difference time domain (FDTD) calculations can be used in the modeling of extremely short external cavity (ESEC) lasers. We concentrate on the applications of ESEC lasers in modern optical data storage systems: we study the operation of direct semiconductor laser read/write heads that utilize either a conventional edge emitting laser or very small aperture laser. The storage medium is assumed to be a first-surface-recorded phase change (e.g. SGT) disc. The external cavity is formed between laser's front facet and disc. The length of the ESEC is typically 0.1 to 1.0 microns. By using FDTD we can study the behavior of the electric field in the ESEC in detail, taking into account the vector field effects resulting from the three-dimensional nature of the data marks and laser apertures. We calculate the distributions of electric field amplitudes, power flow and absorption in/near the external cavity. In addition, we calculate the effective reflectance spectrum of the ESEC and use this data as input into a phenomenological laser model to simulate the readout signal (i.e. laser's output power and/or wavelength) as the disk is scanned. One-dimensional FDTD models were used for qualitative analysis of ESEC laser's wavelength and power characteristics.