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Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection
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Nonlinear optical absorption in a graphene infrared photodetector
Prarthana Gowda1, Dipti R Mohapatra, Abha Misra
1Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore, India 560012.
Nanotechnology
|July 31, 2014
Summary
This study reveals a novel sinusoidal photoresponse in graphene photodetectors, dependent on incident angle and power. Understanding these optical parameters enhances photodetector performance.
Area of Science:
- Optoelectronics
- Materials Science
- Condensed Matter Physics
Background:
- Graphene photodetectors offer promising performance for infrared detection.
- Understanding the optical parameter dependence is crucial for device optimization.
Purpose of the Study:
- To investigate the photoresponse of graphene photodetectors under varying optical parameters.
- To elucidate the underlying mechanisms governing the observed photoresponse.
Main Methods:
- Experimental characterization of graphene photodetector response.
- Systematic variation of infrared incident angle and power.
- Analysis of photoresponse based on charge carrier dynamics and thermal effects.
Main Results:
- A previously unobserved sinusoidal dependence of photoresponse on incidence angle was revealed.
- Nonlinear optical absorption at lower incident power is attributed to photoexcited carriers and photon drag.
- At higher incident power, thermal effects induce deviations in the photoresponse.
Conclusions:
- The photoresponse of graphene photodetectors is highly tunable by optical parameters.
- The study provides new insights into nonlinear optical absorption mechanisms in graphene.
- This work demonstrates the potential for optimizing graphene photodetectors through controlled optical parameter variations.
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