07. May 2024, 16:00 until 17:00

Fabian Garmroudi, TU Wien, Institute of Solid State Physics

Seminar

Entering the metal age: Towards high thermoelectric performance via interband scattering

 

Thermoelectric (TE) materials hold high hopes for various important applications such as converting waste heat into electricity or targeted and efficient cooling. Although historically, the TE effect was first discovered in simple metals more than 200 years ago, researchers nowadays focus on highly complex semiconductors. Here, the primary focus lies on reducing the lattice thermal conductivity down to the amorphous limit via different approaches. However, as a downside, crystallographic and chemical features yielding ultralow often go hand in hand with poor structural, mechanical and thermal stability.

The stringent requirement to reduce does not apply to good metallic conductors (like Cu) which often show electron-dominated instead of lattice-dominated heat transport. In such systems, the dimensionless figure of merit zT, which determines the efficiency of TE devices, solely depends on the Seebeck coefficient (voltage per temperature gradient). This reduces the multidimensional optimization problem of increasing zT to a single tuning parameter. In my talk, I will discuss a novel paradigm to boost the vanishingly small Seebeck coefficient of metals via interband scattering. When two (or more) electronic bands overlap in a certain energy interval, charge carriers can be scattered from one band into the othe r, resulting in a strongly energy-dependent relaxation time. Such electronic interband transitions can be leveraged through disorder and impurities or by lattice vibrations. I will highlight key features in the phonon and electron dispersions [... cont].

Calendar entry

Event location

SEM.R. DB gelb 05 B
1040 Wien
Wiedner Hauptstraße 8-10/E134

 

Organiser

IAP
Manuela Marik
marik@iap.tuwien.ac.at

 

Public

Yes

 

Entrance fee

No

 

Registration required

No