What can we learn from the temperature dependence of carrier mobility?

Event Date
Monday, 14 February 2022 - 12:00pm
Speaker/host external
Alexander Ganose
Type
Online

What can we learn from the temperature dependence of carrier mobility?

Dr Alexander Ganose, Department of Materials 

Date: Monday 14th February 2022

Time: 12.00

 

Click here to join the Seminar  

The temperature dependence of carrier mobility is commonly used to gain insight into the physics of carrier transport - for example, it is used to predict the dominant scattering mechanism limiting the transport of free carriers, fit deformation potentials and effective masses, and to obtain estimates of the optimal doping concentration and temperatures that maximise thermoelectric performance.

In this presentation, I introduce a new, computationally efficient approach for calculating transport in semiconductors, and use it to obtain the transport properties of 24,000 materials. I demonstrate that the temperature dependence of mobility is not a reliable indicator of the dominant scattering mechanism. Furthermore, I reveal that many materials long considered to be dominated by deformation-potential scattering are instead controlled by polar optical phonons. Finally, I highlight the pitfalls of predicting the major scattering type based on the experimental mobility trend alone.

 

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