Abstract: Graphene has emerged as an alternative saturable absorber to other semiconductors due to its nearly constant broadband absorption of 2.3%. It has been shown that graphene and graphene-based nanomaterials can be used as efficient saturable absorbers to generate ultrashort pulses from lasers operating in the near- and mid-infrared. However, the 2.3% absorption of the monolayer graphene introduces operational challenges to the lasers with low gains. To obviate such challenges, the Fermi level position of the graphene can be varied to control the amount of absorption at the desired wavelength. For this purpose, chemically- or electrostatically-doped novel graphene architectures with reduced optical insertion losses can be used to optimize the power performance of the femtosecond lasers.

In this talk, the use of carbon-based saturable absorbers to generate ultrashort pulses from solid-state lasers will be presented and their current drawbacks will be discussed. This will be followed by the overview of the possible approaches, which have been demonstrated to shift the Fermi level of graphene to control the amount of absorption at the desired wavelength. At this point, the voltage-controlled graphene-based supercapacitor architectures proposed by our groups will be demonstrated and the femtosecond pulse generation results obtained with these devices will be discussed.

In the remainder part of the talk, Dr. Baylam will give information about the opportunities provided by The Optical Society (OSA) to the graduate students and early career researchers.