Physics of photonic semiconductor devices

Summary

Series of lectures covering the physics of quantum heterostructures, dielectric microcavities and photonic crystal cavities as well as the properties of the main light emitting devices that are light-emitting diodes (LEDs) and laser diodes (LDs).

Content

Learning Prerequisites

Required courses

Semiconductor physics and light-matter interaction (PHYS-433)

Quantum physics I and II (Bachelor)

Solid State Physics I and II (Bachelor), Quantum Electrodynamics and Quantum Optics (Master)

Learning Outcomes

• Sketch and explain the band diagram of quantum engineered heterostructures (quantum wells, superlattices, quantum dots) subjected or not to an electric field
• Explain the impact of the dimensionality of a semiconductor on excitonic properties
• Assess / Evaluate Evaluate - the properties of single photon emitters and entangled photon sources made from semiconductor quantum dots
• Use basic notions of quantum optics to classify light emitters: assessment of the coherence of a light-source via photon statistics (2nd-order correlation measurements)
• Explain the origin of the enhancement of the spontaneous emission rate via the Purcell effect
• Assess / Evaluate the performance of dielectric cavities (microcavities and photonic crystal slabs) in terms of quality factor and photon lifetime, Lambertian vs non-Lambertian light emission spectra
• Assess / Evaluate the performance of LEDs: internal quantum efficiency, extraction efficiency, wall-plug efficiency, luminous efficiency, color rendering index of white light sources
• Link the radiative and nonradiative carrier lifetimes to microscopic recombination paths in the framework of the ABC model (Shockley-Read-Hall, bimolecular recombination coefficient and Auger term)
• Explain the operating behavior of light-emitting diodes and laser diodes by relying on rate equations
• Compute the material gain of bulk semiconductors and quantum wells (notions of transparency and threshold currents, modal gain)
• Assess / Evaluate the performance of laser diodes: output power, internal quantum efficiency, wall-plug efficiency
• Explain the origin of the temporal coherence of laser diodes (narrow linewidth) and their modulation frequency (several Gbit/s for telecom applications)
• Distinguish the main features of edge-emitting laser diodes and vertical cavity surface emitting lasers

Transversal skills

• Use a work methodology appropriate to the task.
• Plan and carry out activities in a way which makes optimal use of available time and other resources.
• Communicate effectively with professionals from other disciplines.
• Take feedback (critique) and respond in an appropriate manner.
• Summarize an article or a technical report.
• Access and evaluate appropriate sources of information.
• Demonstrate a capacity for creativity.
• Demonstrate the capacity for critical thinking

Teaching methods

Ex cathedra with exercises

Expected student activities

Weekly graded homeworks to secure 1 point out of 6 (16.6% of the final grade)
Read the bibliographical ressources in order to fully integrate and properly use the physical concepts seen in the lectures
and the exercices

Assessment methods

Written exam (with 1 point out of 6 earned via compulsory weekly homeworks (16.6%))

Supervision

Resources

Bibliography

Optoelectronics, Rosencher and Vinter, Cambridge University Press

Notes/Handbook

"Optoelectronics", E. Rosencher & B. Vinter (Cambridge University Press, Cambridge, 2002)
"Wave mechanics applied to semiconductor heterostructures", G. Bastard (Les éditions de physiques, Les Ulis, 1991)
"Optical processes in semiconductors", J. I. Pankove (Dover, New York, 1971)
"Diode lasers and photonic integrated circuits", L. A. Coldren & S. W. Corzine (John Wiley & Sons, Inc., New York, 1995)

Websites

• http://library.epfl.ch/en/beast?isbn=0486602753
• http://library.epfl.ch/en/beast?isbn=9780511754647
• http://library.epfl.ch/en/beast?isbn=2868830927
• http://library.epfl.ch/en/beast?isbn=9780470484128

Moodle Link

• https://go.epfl.ch/PHYS-434