Contact Persons:
Hitesh Sahoo | Building 345A, Room 266 | 4525 6342 | hikus@fotonik.dtu.dk
Kresten Yvind | Building 345A, Room 174| 4525 6366 | kryv@fotonik.dtu.dk
Join us for an exciting project on the simulation of VCSEL structures for a wavelength tunable micro-electro-mechanical-system (MEMS) vertical-cavity-surface-emitting laser (VCSEL). MEMS-VCSELs have applications within telecommunication, medical diagnosis and food analysis for which their single-mode output and fast sweep rate is highly advantageous [1, 2]. We have realized an electrically pumped rapidly tunable MEMS-VCSEL with a centre wavelength of 1060 nm [3] and an optical pumped device (fig 1) for wavelengths above for 1300nm, which allow bidirectional actuation of the movable mirror. Simulation of the many interacting systems is the first step in the device design but also the detailed driving conditions benefit from physical modeling of the device. The devices are fairly complex coupled opto-electro-mechanical systems but to a large extent the different elements can be simulated independently.
The structures simulated in the project will be used in MEMS VCSELs for applications in near-infrared spectroscopy (NIRS) and optical coherence tomography (OCT).
Come talk to us if you are interested and we can tailor the project to your interests and qualifications. If desired the calculations can be combined with measurements.
Goals:
- Accurate simulations of different aspects of MEMS VCSELs (see fig 2-4) including improving on the existing codes.
- Derive parameters and provide inputs for device fabrication and operation.
Skills/Knowledge Acquired:
- Understanding of the underlying physics of the devices
- Physical modeling of Simulation of VCSELs using Modal Method
- MATLAB/COMSOL/Python programming.
Background Requirement:
- Basics of semiconductors/lasers/or mechanics
- Knowledge of MATLAB is an advantage
[1] B. Potsaid ; V. Jayaraman ; J. G. Fujimoto ; J. Jiang ; P. J. S. Heim ; A. E. Cable, “MEMS tunable VCSEL light source for ultrahigh speed 60kHz - 1MHz axial scan rate and long range centimeter class OCT imaging”, SPIE Proceedings 8213 2012.
[2] G. Totschnig, M. Lackner, R. Shau, M. Ortsiefer, J. Rosskopf, M.C. Amann, F. Winter, “High-speed vertical-cavity surface-emitting laser (VCSEL) absorption spectroscopy of ammonia (NH3) near 1.54 μm”, Applied Physics B, vol. 76, no. 5, pp. 603-608, 2003.
[3] T. Ansbæk, I.-S. Chung, E. Semenova, K. Yvind, “1060 nm Tunable Monolithic High Index Contrast Subwavelength Grating Vertical-Cavity Surface-Emitting Laser “, IEEE Photon. Techn. Lett., 2013.